The bulk of the MIDAS AJAX and Javascript functions is now documented on the MIDAS Wiki:

https://midas.triumf.ca/MidasWiki/index.php/Mhttpd.js
https://midas.triumf.ca/MidasWiki/index.php/AJAX

Enjoy,
K.O.

> The bulk of the MIDAS AJAX and Javascript functions is now documented on the MIDAS Wiki:
> 
> https://midas.triumf.ca/MidasWiki/index.php/Mhttpd.js
> https://midas.triumf.ca/MidasWiki/index.php/AJAX
> 

The documentation was updated again.

All functions and AJAX methods except jset, jget, jrpc (ODBGet, ODBSet, ODBRpc) and inline edit are now fully 
documented. AJAX methods jset/jget and their javascript wrappers ODBSet/ODBGet/ODBMGet/ODBGetRecord() are 
partially documented. Inline edit will have to be documented by Stefan.

When using these functions please read the "BUG" sections carefully.

When using the Javascript functions (ODBGet, ODBSet, ODBMCopy, etc) please pay special attention to the rules for URI-
encoding function arguments - some functions require that some arguments be pre-encoded by 
"encodeURIComponent()", some functions require some arguments to NOT be pre-encoded. The examples in 
examples/javascript1/example.html are mostly correct.

Special confusion is created by special handling in mhttpd of URI-encoding of parameters named "format".

Special confusion is created by ODBSet(path, value), where "path" should be pre-encoded, while "value" is now encoded 
internally, which is a recent change introduced with the inline edit function. Older versions of mhttpd.js still require that 
"value" be URI-encoded.

Going forward, I hope to resolve most of the confusion by providing a cleaner interface for reading ODB
- ODBMCopy() already looks good with full async JSON/JSONP support (already implemented)
- ODBMKey() to read just the keys, with async JSON/JSONP support (to be added)
- ODBMCreate() to create ODB keys (RPC for db_create()) (to be added)
- ODBMSet() to write into ODB. (to be added)

K.O.

> > The bulk of the MIDAS AJAX and Javascript functions is now documented on the MIDAS Wiki:
> > 
> > https://midas.triumf.ca/MidasWiki/index.php/Mhttpd.js
> > https://midas.triumf.ca/MidasWiki/index.php/AJAX
> > 
> 
> The documentation was updated again.
> 

Newly documented are the additional Javascript and AJAX functions present in the GIT branch "feature/ajax":

ODBMCreate(paths, types);
ODBMCreate(paths, types, arraylengths, stringlengths, callback);  
ODBMResize(paths, arraylengths, stringlengths, callback);  
ODBMRename(paths, names, callback);  
ODBMLink(paths, links, callback);  
ODBMReorder(paths, indices, callback);
ODBMKey(paths, callback);
ODBMDelete(paths, callback);

All these functions permit asynchronous use (with callback on completion) and the underlying AJAX functions permit JSON-P encoding.

ODBSetUrl("http://mhttpd.somewhere.com:8080") : this new function removes the restriction that custom scripts had to be loaded from the same mhttpd that they will 
access. Together with the newly added CORS support in mhttpd, allows loading custom scripts from any web server, including local file, and having then access any one (or 
any several) mhttpd data sources.

I think these new functions are now stable (I still had to make some changes to ODBMCreate() recently) and after some more testing this branch will be merged into 
"develop".

To use this branch, do either:
a) git clone midas; git pull; git checkout feature/ajax
b) git clone midas; git checkout develop; git pull; git checkout -b ajaxtest; git merge feature/ajax;

(Option (b) creates a local branch with the latest "develop" and "feature/ajax" merged together).

K.O.

The general Midas documentation has been rejuvenated by Suzannah Daviel through 
a proof reading and with a collection of custom perl scripts to improve the 
Doxygen capabilities for the document itself. In particular, a contents list and 
alphabetical index of the documentation is generated automatically.

The new content is based on the previous version but with more cross-references, 
examples and descriptive images where necessary. Many of the previously 
undocumented features are now included.

The layout and organization is slightly different and requires getting used to, 
but hopefully will be an improvement.
Some of the changes are:
- The main topics are maintained, but we try to regroup all the aspects
  related to a particular topic in the same section.
- The Yellow icons provide navigation within the index section.
- The Blue icons provide navigation within the section content.

The full documentation is included under the midas/doc/src directory in the 
Midas distribution (SVN) and can be generated with the Doxygen tool.
The midasdoc-images.tar.gz from either https://midas.psi.ch/download/ or 
http://ladd00.triumf.ca/~daqweb/ftp/ needs to be extracted to the midas 
directory under doc/images for complete local web pages generation.

There are a few "ToDo" items which hopefully will be ironed out soon.
Feel free to contact us for pointing out omissions or improvements.

We hope this online documentation will serve as a better tool for your 
understanding of the Midas capabilities.

I found where we tickle the race condition in db_create_record().

1) in mhttpd.c,  every time we show the status page, we call
db_create_record(hDB, 0, "/Runinfo", strcomb(runinfo_str));
2) internally db_create_record() deletes /RunInfo
3) other programs read "/runinfo/run number" while it is deleted do not
check for the db_get_value() error code and happily get a zero run number.

Stephan fixed the race condition, and now I commited an mhttpd.c change that
only calls db_create_record(hDB, 0, "/Runinfo", strcomb(runinfo_str)); if
/runinfo does not exist. This seems to be redundant with a similar call in
cm_connect_experiment1(), called each time a new client starts up.

Files changed:
src/mhttpd.c

K.O.

> I found where we tickle the race condition in db_create_record().
> 
> 1) in mhttpd.c,  every time we show the status page, we call
> db_create_record(hDB, 0, "/Runinfo", strcomb(runinfo_str));
> 2) internally db_create_record() deletes /RunInfo
> 3) other programs read "/runinfo/run number" while it is deleted do not
> check for the db_get_value() error code and happily get a zero run number.
> 
> Stephan fixed the race condition, and now I commited an mhttpd.c change that
> only calls db_create_record(hDB, 0, "/Runinfo", strcomb(runinfo_str)); if
> /runinfo does not exist. This seems to be redundant with a similar call in
> cm_connect_experiment1(), called each time a new client starts up.

The reason for the db_create_record() is the following: Assume that we change 
the /runinfo structure, by adding an additional variable in the future. If we 
run a "new" mhttpd on an "old" experiment, the "runinfo" C structure does not 
match the ODB contents. The db_create_record() ensures that the ODB structure 
exactly matches the C structure. I agree with you that this can cause 
potential problems. But most of them should be fixed by the additional lock() 
I added recently. So other programs cannot read the run number while it is 
deleted.

One could think of checking the record size, and re-creating the runinfo if 
the ODB record size does not match the C record size. But this does not 
prevent the potential error that some variable are reversed in order. They 
are then mapped wrongly to the C runinfo structure.

I see that you work very hard now on all possible checks for the run number. 
But I would not commit that and make it part of the distribution, since all 
experiments at PSI for example do not have this run number problem. Run it 
locally, determine the cause of your problem (the discovery of the race 
condition was already very good, I'm glad that your found it, should make the 
system much more stable), and we'll fix it. Puttin ASSERT's is a good idea, I 
should have done it from the very beginning. But if you start now, please put 
it in all other 100000 places (;-)

I would not add a db_get_value_cannot_possibly_fail() into the standard 
distribution, because it probably cannot correct the initial problem and then 
just will go into an infinite loop. We should tackle problems always at their 
source. 

If you cannot resolve your zero run number problem, do the following: There 
is a cm_msg(MDEBUG, ...) which only puts a message into the shared memory, 
but not in midas.log. This can be used for real time debugging. Add those 
message temporarily in db_get_value() etc. to see what is going on. As soon 
as the run number goes to zero, stop all processes immediately (for example 
by locking the database with db_lock_database), and the look backwards in the 
sysmsg buffer to see what happened *before* the run number went to zero.

- Stefan

> > I found where we tickle the race condition in db_create_record().
> The reason for the db_create_record() is the following: Assume that we change 
> the /runinfo structure...

I think there is a deep fundamental problem with changing data structures "on the
fly". Calling db_create_record("/runinfo") at every show_status_page() does not
fix it.

If I change the runinfo structure, rebuild, relink and restart "mhttpd", the
db_create_record("/runinfo") from cm_connect_experiment() will update the runinfo
structure in ODB. In this case, the call from show_status_page() is redundant. As
a side effect, when we do this, we break every running ODB client- they still
have the old runinfo layout. Not good...

If I change the runinfo structure, rebuild, relink and restart all applications,
*except* for mhttpd, "/runinfo" in ODB will be updated when the first updated
client connects to ODB via the db_create_record("/runinfo") from
cm_connect_experiment(). Then, the old mhttpd will restore the old layout via the 
db_create_record("/runinfo") in show_status_page(), breaking everything. Not good...

If I change the runinfo structure, rebuild, relink and restart everything,
"/runinfo" in ODB will be updated when the first client connects to ODB via the
db_create_record("/runinfo") from cm_connect_experiment(). In this case, the call
from show_status_page() is redundant. This is the only corruption-free scenario.

This lack of integrity enforcement vs version skew in binary data structures is,
I think, an ODB design error. Perhaps, ODB applications should be prohibited from
 direct access to ODB "C" data structures: we cannot ensure that the data layout
in the application and in ODB are the same.

> One could think of checking the record size, and re-creating the runinfo if 
> the ODB record size does not match the C record size. But this does not 
> prevent the potential error that some variable are reversed in order. They 
> are then mapped wrongly to the C runinfo structure.

Exacto.

> I see that you work very hard now on all possible checks for the run number. 
> But I would not commit that and make it part of the distribution...

This is a philosophical issue.

My checks are in line with the "design by contract" school of programming. In a
nutshell, this ideology requires that before I do anything, I should enforce the
validity of my inputs and after I am done, I should enforce the validity of my
outputs. In practice, this translates into liberal use of assert()'s *in
production code*.

To ensure that old bugs stay fixed, and that new bugs are promptly discovered, it
is essential that the "contract checks" stay in the production code forever.

But let better writers argue programming philosophy in the literature.

Personally, when hunting down bugs in unstable code, I find this technique to be
vastly superior to the more common appoach of "This program has no bugs. Error
checking and assert()s are wasteful. Let's close our eyes and hope no bad things
happen to us (again)".

> But if you start now, please put [asserts] in all other 100000 places (;-)

I know that no good deed goes unpunished, but pewleeze!!!

> If you cannot resolve your zero run number problem, do the following: ...
> [lock ODB, freeze the experiment, look at log files]

This technique is obsolete. Today, we instrument the code with sanity checks
and validity tests. Then all the bugs find themselves with minimal manual
intervention.

K.O.

The default C indentation style in xemacs uses "tab" characters, violating
the MIDAS coding convention. To disable this misfeature in xemacs (emacs
too?), put this incantation in your .xemacs/custom.el file:

(custom-set-variables
 '(indent-tabs-mode nil))

K.O.

We're trying to install the SuperCDMS version of MIDAS on a Rocky 9.4 Virtual 
Machine and are getting a persistent error when we run mserver.  As far as I 
know there are minimal changes between this and the MIDAS branch, but Ben Smith 
may have more to say on this.

[lekhraj@sdfcdmsdaq online]$ mserver
mserver started interactively
[mserver,INFO] Client 'ODBEdit' on buffer 'SYSMSG' removed by bm_open_buffer 
because process pid 481051 does not exist
mserver will listen on TCP port 1175
[mserver,ERROR] [odb.cxx:2498:db_lock_database,ERROR] cannot lock ODB semaphore, 
timeout 10000 ms, exiting...
[mserver,ERROR] [midas.cxx:2205:cm_check_connect,ERROR] cm_disconnect_experiment 
not called at end of program
db_lock_database: Detected recursive call to db_{lock,unlock}_database() while 
already inside db_{lock,unlock}_database(). Maybe this is a call from a signal 
handler. Cannot continue, aborting...
Aborted (core dumped)

We thought perhaps we had a corrupted ODB file, so we removed the ODB file and 
tried to create a new one (sized correctly for our experiment):

[lekhraj@sdfcdmsdaq online]$ odbedit -s 50000000
[ODBEdit,ERROR] [odb.cxx:2052:db_open_database,ERROR] Removed ODB client 
'mserver', index 0 because process pid 481326 does not exists
[ODBEdit,INFO] Removed open record flag from "/Experiment/Security/RPC 
hosts/Allowed hosts"
[ODBEdit,INFO] Removed exclusive access mode from "/Experiment/Security/RPC 
hosts/Allowed hosts"
[ODBEdit,INFO] Corrected 1 ODB entries
[ODBEdit,INFO] Deleted entry '/System/Clients/481326' for client 'mserver' 
because it is not connected to ODB
[ODBEdit,INFO] Client 'mserver' on buffer 'SYSMSG' removed by bm_open_buffer 
because process pid 481326 does not exist
[local:test:S]/>Bus error (core dumped)

> We're trying to install the SuperCDMS version of MIDAS on a Rocky 9.4 Virtual 
> Machine and are getting a persistent error when we run mserver.  As far as I 
> know there are minimal changes between this and the MIDAS branch, but Ben Smith 
> may have more to say on this.

For reference, "the SuperCDMS version of MIDAS" is just a fork that no longer has any meaningful differences vs the main MIDAS repo, but we only pull updates infrequently after testing a bunch. We last pulled from the develop branch in November 2023. But that should be irrelevant here as semaphore code hasn't been touched for a very long time.

We're running Alma 9.4 on a machine at TRIUMF and the same version of midas works fine there (Amy, you may already have access to scdms-zeus). I believe Alma and Rocky should be basically identical for this.

So the questions are:
* Have you tried other midas programs, or only mserver? E.g. did odbedit and mhttpd work?
* If other programs work, have you been running them all as the same user? In particular, if you ran one program as root and another as an unprivileged user, then you will likely get odd permissions issues.
* What do you see if you run `ls -l /dev/shm` and `ls -l ~/packages/SuperCDMS_DAQ/MidasDAQ/online/.*SHM`? (Or wherever your online dir is for the 2nd one).
* Did you follow the full instructions for recovering from a corrupt ODB? https://daq00.triumf.ca/MidasWiki/index.php/FAQ#How_to_recover_from_a_corrupted_ODB   In particular the bit about running odbinit with the --cleanup flag?

> We're trying to install the SuperCDMS version of MIDAS on a Rocky 9.4 Virtual 
> Machine and are getting a persistent error when we run mserver.
>
> [mserver,ERROR] [odb.cxx:2498:db_lock_database,ERROR] cannot lock ODB semaphore, 
> timeout 10000 ms, exiting...
> db_lock_database: Detected recursive call to db_{lock,unlock}_database() while 
> already inside db_{lock,unlock}_database(). Maybe this is a call from a signal 
> handler. Cannot continue, aborting...
> Aborted (core dumped)

This is super very bad. Since you have a core dump, please post the stack trace here (or email it to me).

I probably cannot debug your private version of midas and I will recommend that you install and run vanilla midas 
mserver (just while we debug this problem).

Let's look at the core dump stack trace first, but likely we see a problem with System-V semaphores and hopefully it 
is not some breakage due to Red Hat bogosity or due to something specific to running on a virtual machine.

If indeed this is Linux-kernel level breakage of System-V semaphores, solution would be to start using Posix 
semaphores, something I wanted to do for a long time. We already switched MIDAS shared memory from System-V to Posix 
shared memory.

If we are lucky it is just one more crasher bug in ODB. Let's see that core dump stack trace.

K.O.

We run Midas with no problems on Rocky 9.4, although not in a virtual machine.  We're very close to the head of `develop`.

I'm fairly sure I've seen an error like this before.  I didn't pay it much attention because it was transitory and I was doing something weird at the time - probably 
stepping through with a debugger and hit a timeout.  It was definitely about an ODB semaphore but I can't recall if it was about a recursive call.

Basically I think Rocky 9.4 is a red herring.  Do you have another crashed copy of mserver/mhttpd running somewhere and stuck in limbo?  If it's a virtual machine 
are you sharing the shared memory location with the host, and running another midas on there?


> > We're trying to install the SuperCDMS version of MIDAS on a Rocky 9.4 Virtual 
> > Machine and are getting a persistent error when we run mserver.
> >
> > [mserver,ERROR] [odb.cxx:2498:db_lock_database,ERROR] cannot lock ODB semaphore, 
> > timeout 10000 ms, exiting...
> > db_lock_database: Detected recursive call to db_{lock,unlock}_database() while 
> > already inside db_{lock,unlock}_database(). Maybe this is a call from a signal 
> > handler. Cannot continue, aborting...
> > Aborted (core dumped)
> 
> This is super very bad. Since you have a core dump, please post the stack trace here (or email it to me).
> 
> I probably cannot debug your private version of midas and I will recommend that you install and run vanilla midas 
> mserver (just while we debug this problem).
> 
> Let's look at the core dump stack trace first, but likely we see a problem with System-V semaphores and hopefully it 
> is not some breakage due to Red Hat bogosity or due to something specific to running on a virtual machine.
> 
> If indeed this is Linux-kernel level breakage of System-V semaphores, solution would be to start using Posix 
> semaphores, something I wanted to do for a long time. We already switched MIDAS shared memory from System-V to Posix 
> shared memory.
> 
> If we are lucky it is just one more crasher bug in ODB. Let's see that core dump stack trace.
> 
> K.O.

> > We're trying to install the SuperCDMS version of MIDAS on a Rocky 9.4 Virtual 
> > Machine and are getting a persistent error when we run mserver.  As far as I 
> > know there are minimal changes between this and the MIDAS branch, but Ben Smith 
> > may have more to say on this.
> 
> For reference, "the SuperCDMS version of MIDAS" is just a fork that no longer has any meaningful differences vs the main MIDAS repo, but we only pull updates infrequently after testing a bunch. We last pulled from the develop branch in November 2023. But that should be irrelevant here as semaphore code hasn't been touched for a very long time.
> 
> We're running Alma 9.4 on a machine at TRIUMF and the same version of midas works fine there (Amy, you may already have access to scdms-zeus). I believe Alma and Rocky should be basically identical for this.
> 
> So the questions are:
> * Have you tried other midas programs, or only mserver? E.g. did odbedit and mhttpd work?
> * If other programs work, have you been running them all as the same user? In particular, if you ran one program as root and another as an unprivileged user, then you will likely get odd permissions issues.
> * What do you see if you run `ls -l /dev/shm` and `ls -l ~/packages/SuperCDMS_DAQ/MidasDAQ/online/.*SHM`? (Or wherever your online dir is for the 2nd one).
> * Did you follow the full instructions for recovering from a corrupt ODB? https://daq00.triumf.ca/MidasWiki/index.php/FAQ#How_to_recover_from_a_corrupted_ODB   In particular the bit about running odbinit with the --cleanup flag?

Here's what happens when I try to run odbedit:

[lekhraj@sdfcdmsdaq setup]$ odbedit
[ODBEdit,ERROR] [odb.cxx:2052:db_open_database,ERROR] Removed ODB client 'ODBEdit', index 0 because process pid 481823 does not exists
[ODBEdit,INFO] Removed open record flag from "/Experiment/Security/RPC hosts/Allowed hosts"
[ODBEdit,INFO] Removed exclusive access mode from "/Experiment/Security/RPC hosts/Allowed hosts"
[ODBEdit,INFO] Corrected 1 ODB entries
[ODBEdit,INFO] Deleted entry '/System/Clients/481823' for client 'ODBEdit' because it is not connected to ODB
[ODBEdit,INFO] Client 'ODBEdit' on buffer 'SYSMSG' removed by bm_open_buffer because process pid 481823 does not exist
[ODBEdit,ERROR] [odb.cxx:2498:db_lock_database,ERROR] cannot lock ODB semaphore, timeout 10000 ms, exiting...
[ODBEdit,ERROR] [midas.cxx:2205:cm_check_connect,ERROR] cm_disconnect_experiment not called at end of program
db_lock_database: Detected recursive call to db_{lock,unlock}_database() while already inside db_{lock,unlock}_database(). Maybe this is a call from a signal handler. Cannot continue, aborting...
Aborted (core dumped)
[lekhraj@sdfcdmsdaq setup]$

And mhttpd:

[lekhraj@sdfcdmsdaq setup]$ mhttpd
[mhttpd,ERROR] [odb.cxx:2052:db_open_database,ERROR] Removed ODB client 'ODBEdit', index 0 because process pid 601054 does not exists
[mhttpd,INFO] Removed open record flag from "/Experiment/Security/RPC hosts/Allowed hosts"
[mhttpd,INFO] Removed exclusive access mode from "/Experiment/Security/RPC hosts/Allowed hosts"
[mhttpd,INFO] Corrected 1 ODB entries
[mhttpd,INFO] Deleted entry '/System/Clients/601054' for client 'ODBEdit' because it is not connected to ODB
[mhttpd,INFO] Client 'ODBEdit' on buffer 'SYSMSG' removed by bm_open_buffer because process pid 601054 does not exist
[mhttpd,INFO] ODB subtree /Runinfo corrected successfully
Password protection is off
Hostlist off, connections from anywhere will be accepted
Listening on "http://localhost:8080", passwords OFF, hostlist OFF
Listening on "http://[::1]:8080", passwords OFF, hostlist OFF
bm_lock_buffer: Lock buffer "SYSMSG" is taking longer than 1 second!
[mhttpd,ERROR] [odb.cxx:2498:db_lock_database,ERROR] cannot lock ODB semaphore, timeout 10000 ms, exiting...
[mhttpd,ERROR] [midas.cxx:2205:cm_check_connect,ERROR] cm_disconnect_experiment not called at end of program
db_lock_database: Detected recursive call to db_{lock,unlock}_database() while already inside db_{lock,unlock}_database(). Maybe this is a call from a signal handler. Cannot continue, aborting...
Aborted (core dumped)
[lekhraj@sdfcdmsdaq setup]$

We have been running everything as a single user, the user who cloned the repositories and owns the directories.

We did follow the corrupted-ODB cleanup instructions.

[lekhraj@sdfcdmsdaq setup]$ ls -lh /dev/shm
total 1.3M
-rw------- 1 lekhraj dm 1.2M Oct  8 14:13 17468_test_ODB__sdf_home_l_lekhraj_packages_SuperCDMS_DAQ_MidasDAQ_online_
-rw------- 1 lekhraj dm 114K Oct  7 14:06 17468_test_SYSMSG__sdf_home_l_lekhraj_packages_SuperCDMS_DAQ_MidasDAQ_online_

[lekhraj@sdfcdmsdaq setup]$ ls -lh ~/packages/SuperCDMS_DAQ/MidasDAQ/online/.*SHM
-rw-r--r-- 1 lekhraj dm    0 Oct  3 08:46 /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/MidasDAQ/online/.ALARM.SHM
-rw-r--r-- 1 lekhraj dm    0 Oct  3 08:46 /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/MidasDAQ/online/.ELOG.SHM
-rw-r--r-- 1 lekhraj dm    0 Oct  3 08:46 /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/MidasDAQ/online/.HISTORY.SHM
-rw-r--r-- 1 lekhraj dm    0 Oct  3 08:46 /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/MidasDAQ/online/.LAZY.SHM
-rw-r--r-- 1 lekhraj dm    0 Oct  3 08:46 /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/MidasDAQ/online/.MSG.SHM
-rw-r--r-- 1 lekhraj dm 1.2M Oct  8 14:12 /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/MidasDAQ/online/.ODB.SHM
-rw-r--r-- 1 lekhraj dm    0 Oct  3 08:46 /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/MidasDAQ/online/.SYSMSG.SHM
-rw-r--r-- 1 lekhraj dm    0 Oct  3 08:46 /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/MidasDAQ/online/.SYSTEM.SHM

> > We're trying to install the SuperCDMS version of MIDAS on a Rocky 9.4 Virtual 
> > Machine and are getting a persistent error when we run mserver.
> >
> > [mserver,ERROR] [odb.cxx:2498:db_lock_database,ERROR] cannot lock ODB semaphore, 
> > timeout 10000 ms, exiting...
> > db_lock_database: Detected recursive call to db_{lock,unlock}_database() while 
> > already inside db_{lock,unlock}_database(). Maybe this is a call from a signal 
> > handler. Cannot continue, aborting...
> > Aborted (core dumped)
> 
> This is super very bad. Since you have a core dump, please post the stack trace here (or email it to me).
> 
> I probably cannot debug your private version of midas and I will recommend that you install and run vanilla midas 
> mserver (just while we debug this problem).
> 
> Let's look at the core dump stack trace first, but likely we see a problem with System-V semaphores and hopefully it 
> is not some breakage due to Red Hat bogosity or due to something specific to running on a virtual machine.
> 
> If indeed this is Linux-kernel level breakage of System-V semaphores, solution would be to start using Posix 
> semaphores, something I wanted to do for a long time. We already switched MIDAS shared memory from System-V to Posix 
> shared memory.
> 
> If we are lucky it is just one more crasher bug in ODB. Let's see that core dump stack trace.
> 
> K.O.

I've uploaded the current core dump at: https://gitlab.com/det-lab/coredumps#.

This was done using the "CDMS" version of MIDAS, I'll compile the current MIDAS repository just to be sure we're seeing 
the same error and report back here!

> I've uploaded the current core dump at: https://gitlab.com/det-lab/coredumps#.

I cannot read the core dump without the corresponding executable (and likely all it's shared libraries).

It is best if you run gdb and extract the stack traces on your end.

In case you are not familiar with gdb:

gdb mserver core # start gdb
bt # stack trace of crashed thread
info thr # get list of threads
thr 1
bt
thr 2
bt
# etc, get stack trace of each thread, there should not be too many of them

K.O.

I read these error messages. There is no ODB corruption. ODB semaphore is locked and all midas programs will fail, they will timeout trying to get the lock, report the timeout, then it looks like a bug was introduced where instead of hard exit or abort() they attempt a clean shutdown which crashes from a recursive call in db_lock_database(). Amy's 
core dump should confirm this.

K.O.


> > > We're trying to install the SuperCDMS version of MIDAS on a Rocky 9.4 Virtual 
> > > Machine and are getting a persistent error when we run mserver.  As far as I 
> > > know there are minimal changes between this and the MIDAS branch, but Ben Smith 
> > > may have more to say on this.
> > 
> > For reference, "the SuperCDMS version of MIDAS" is just a fork that no longer has any meaningful differences vs the main MIDAS repo, but we only pull updates infrequently after testing a bunch. We last pulled from the develop branch in November 2023. But that should be irrelevant here as semaphore code hasn't been touched for a very long time.
> > 
> > We're running Alma 9.4 on a machine at TRIUMF and the same version of midas works fine there (Amy, you may already have access to scdms-zeus). I believe Alma and Rocky should be basically identical for this.
> > 
> > So the questions are:
> > * Have you tried other midas programs, or only mserver? E.g. did odbedit and mhttpd work?
> > * If other programs work, have you been running them all as the same user? In particular, if you ran one program as root and another as an unprivileged user, then you will likely get odd permissions issues.
> > * What do you see if you run `ls -l /dev/shm` and `ls -l ~/packages/SuperCDMS_DAQ/MidasDAQ/online/.*SHM`? (Or wherever your online dir is for the 2nd one).
> > * Did you follow the full instructions for recovering from a corrupt ODB? https://daq00.triumf.ca/MidasWiki/index.php/FAQ#How_to_recover_from_a_corrupted_ODB   In particular the bit about running odbinit with the --cleanup flag?
> 
> Here's what happens when I try to run odbedit:
> 
> [lekhraj@sdfcdmsdaq setup]$ odbedit
> [ODBEdit,ERROR] [odb.cxx:2052:db_open_database,ERROR] Removed ODB client 'ODBEdit', index 0 because process pid 481823 does not exists
> [ODBEdit,INFO] Removed open record flag from "/Experiment/Security/RPC hosts/Allowed hosts"
> [ODBEdit,INFO] Removed exclusive access mode from "/Experiment/Security/RPC hosts/Allowed hosts"
> [ODBEdit,INFO] Corrected 1 ODB entries
> [ODBEdit,INFO] Deleted entry '/System/Clients/481823' for client 'ODBEdit' because it is not connected to ODB
> [ODBEdit,INFO] Client 'ODBEdit' on buffer 'SYSMSG' removed by bm_open_buffer because process pid 481823 does not exist
> [ODBEdit,ERROR] [odb.cxx:2498:db_lock_database,ERROR] cannot lock ODB semaphore, timeout 10000 ms, exiting...
> [ODBEdit,ERROR] [midas.cxx:2205:cm_check_connect,ERROR] cm_disconnect_experiment not called at end of program
> db_lock_database: Detected recursive call to db_{lock,unlock}_database() while already inside db_{lock,unlock}_database(). Maybe this is a call from a signal handler. Cannot continue, aborting...
> Aborted (core dumped)
> [lekhraj@sdfcdmsdaq setup]$
> 
> And mhttpd:
> 
> [lekhraj@sdfcdmsdaq setup]$ mhttpd
> [mhttpd,ERROR] [odb.cxx:2052:db_open_database,ERROR] Removed ODB client 'ODBEdit', index 0 because process pid 601054 does not exists
> [mhttpd,INFO] Removed open record flag from "/Experiment/Security/RPC hosts/Allowed hosts"
> [mhttpd,INFO] Removed exclusive access mode from "/Experiment/Security/RPC hosts/Allowed hosts"
> [mhttpd,INFO] Corrected 1 ODB entries
> [mhttpd,INFO] Deleted entry '/System/Clients/601054' for client 'ODBEdit' because it is not connected to ODB
> [mhttpd,INFO] Client 'ODBEdit' on buffer 'SYSMSG' removed by bm_open_buffer because process pid 601054 does not exist
> [mhttpd,INFO] ODB subtree /Runinfo corrected successfully
> Password protection is off
> Hostlist off, connections from anywhere will be accepted
> Listening on "http://localhost:8080", passwords OFF, hostlist OFF
> Listening on "http://[::1]:8080", passwords OFF, hostlist OFF
> bm_lock_buffer: Lock buffer "SYSMSG" is taking longer than 1 second!
> [mhttpd,ERROR] [odb.cxx:2498:db_lock_database,ERROR] cannot lock ODB semaphore, timeout 10000 ms, exiting...
> [mhttpd,ERROR] [midas.cxx:2205:cm_check_connect,ERROR] cm_disconnect_experiment not called at end of program
> db_lock_database: Detected recursive call to db_{lock,unlock}_database() while already inside db_{lock,unlock}_database(). Maybe this is a call from a signal handler. Cannot continue, aborting...
> Aborted (core dumped)
> [lekhraj@sdfcdmsdaq setup]$
> 
> We have been running everything as a single user, the user who cloned the repositories and owns the directories.
> 
> We did follow the corrupted-ODB cleanup instructions.
> 
> [lekhraj@sdfcdmsdaq setup]$ ls -lh /dev/shm
> total 1.3M
> -rw------- 1 lekhraj dm 1.2M Oct  8 14:13 17468_test_ODB__sdf_home_l_lekhraj_packages_SuperCDMS_DAQ_MidasDAQ_online_
> -rw------- 1 lekhraj dm 114K Oct  7 14:06 17468_test_SYSMSG__sdf_home_l_lekhraj_packages_SuperCDMS_DAQ_MidasDAQ_online_
> 
> [lekhraj@sdfcdmsdaq setup]$ ls -lh ~/packages/SuperCDMS_DAQ/MidasDAQ/online/.*SHM
> -rw-r--r-- 1 lekhraj dm    0 Oct  3 08:46 /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/MidasDAQ/online/.ALARM.SHM
> -rw-r--r-- 1 lekhraj dm    0 Oct  3 08:46 /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/MidasDAQ/online/.ELOG.SHM
> -rw-r--r-- 1 lekhraj dm    0 Oct  3 08:46 /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/MidasDAQ/online/.HISTORY.SHM
> -rw-r--r-- 1 lekhraj dm    0 Oct  3 08:46 /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/MidasDAQ/online/.LAZY.SHM
> -rw-r--r-- 1 lekhraj dm    0 Oct  3 08:46 /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/MidasDAQ/online/.MSG.SHM
> -rw-r--r-- 1 lekhraj dm 1.2M Oct  8 14:12 /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/MidasDAQ/online/.ODB.SHM
> -rw-r--r-- 1 lekhraj dm    0 Oct  3 08:46 /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/MidasDAQ/online/.SYSMSG.SHM
> -rw-r--r-- 1 lekhraj dm    0 Oct  3 08:46 /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/MidasDAQ/online/.SYSTEM.SHM

> Basically I think Rocky 9.4 is a red herring.

This is what likely happened:
- some program crashed while holding the ODB lock semaphore (by ctrl-C at the wrong time or by kill -KILL at the wring time)
- semaphore is locked with a flag "unlock if this program stops"
- this is supposed to ensure ODB lock semaphore never gets stuck in the locked state
- (there is no code in MIDAS to unlock the ODB lock semaphore without locking it first)
- we have observed a malfunction in the Linux kernel, where this automatic unlock does not happen.
- it is rare and so far cannot be reproduced. you can find more about it by searching this forum.
- I think it is a bug in the System-V semaphore code or in the Linux "program stop" code (a path where they fail to call the semaphore unlock handler, and who knows what 
other handlers).
- System-V semaphores are very obsolete, replaced by POSIX semaphores.
- POSIX semaphores do not have the "unlock if this program stops" magic, the user (MIDAS) is responsible with detecting that the program who locked the semaphore is gone 
and and with taking corrective action, i.e. release the lock, automatically.

I do not know if this problem with System-V semaphores is in the generic Linux kernel, or if it is specific
to the Red Hat kernels (they are known to have many patches, deviating quite far from vanilla kernels).

I do not know if this problem is somehow sensitive to virtual machines.

So yes/no, Red Hat derived linux on a virtual machine could be where this problem happens more often that elsewhere.

K.O.

> I read these error messages. There is no ODB corruption. ODB semaphore is locked and all midas programs will fail...

Recovery from this is:
- stop all midas programs (actually they should have all crashed by now)
- identify the ODB semaphore with: ipcs -s -t
- remove the ODB semaphore with: ipcrm sem <semid>
- where <semid> is from the first column of ipcs
- keep deleting semaphores until odbedit works.
- if you delete extra midas sempahores, odbedit will recreate them
- if you delete non-midas semaphores, oh, well...

Little bit better steps for this recovery may be written up by Suzannah in this forum
or in the midas wiki... good luck finding them.

K.O.

> > I've uploaded the current core dump at: https://gitlab.com/det-lab/coredumps#.
> 
> I cannot read the core dump without the corresponding executable (and likely all it's shared libraries).
> 
> It is best if you run gdb and extract the stack traces on your end.
> 
> In case you are not familiar with gdb:
> 
> gdb mserver core # start gdb
> bt # stack trace of crashed thread
> info thr # get list of threads
> thr 1
> bt
> thr 2
> bt
> # etc, get stack trace of each thread, there should not be too many of them
> 
> K.O.

Hi Konstantin, thanks for the instructions.  I do appear to be missing some debug symbols, but the output 
looks potentially useful:

[lekhraj@sdfcdmsdaq ~]$ gdb mserver 
core.mserver.17468.b174bb74f2bb44f9a0905e78ec6b2677.601715.1728422354000000
GNU gdb (GDB) Rocky Linux 10.2-11.1.el9_3
...
For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from mserver...
[New LWP 601715]

warning: Section `.reg-xstate/601715' in core file too small.
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
Core was generated by `mserver'.
Program terminated with signal SIGABRT, Aborted.

warning: Section `.reg-xstate/601715' in core file too small.
#0  0x00007fbdeaca154c in __pthread_kill_implementation () from /lib64/libc.so.6
Missing separate debuginfos, use: dnf debuginfo-install glibc-2.34-83.el9.12.x86_64 libgcc-11.4.1-
3.el9.x86_64 libstdc++-11.4.1-2.1.el9.x86_64 libzstd-1.5.1-2.el9.x86_64 mysql-libs-8.0.36-1.el9_3.x86_64 
openssl-libs-3.0.7-25.el9_3.x86_64 zlib-1.2.11-40.el9.x86_64
(gdb)
(gdb) bt
#0  0x00007fbdeaca154c in __pthread_kill_implementation () from /lib64/libc.so.6
#1  0x00007fbdeac54d06 in raise () from /lib64/libc.so.6
#2  0x00007fbdeac287f3 in abort () from /lib64/libc.so.6
#3  0x0000000000430ee4 in db_lock_database (hDB=hDB@entry=1)
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:2473
#4  0x0000000000437e9c in db_find_key (subhKey=0x7ffcc536d348, key_name=0x4687a8 "/Logger/Message file date 
format",
    hKey=0, hDB=1) at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:4099
#5  db_find_key (hDB=1, hKey=0, key_name=0x4687a8 "/Logger/Message file date format", 
subhKey=0x7ffcc536d348)
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:4075
#6  0x0000000000448297 in db_get_value_string (hdb=1, hKeyRoot=hKeyRoot@entry=0,
    key_name=key_name@entry=0x4687a8 "/Logger/Message file date format", index=index@entry=0,
    s=s@entry=0x7ffcc536d470, create=create@entry=1, create_string_length=0)
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:13950
#7  0x000000000040a690 in cm_msg_get_logfile (fac=<optimized out>, t=<optimized out>, 
filename=0x7ffcc536d690,
    linkname=0x7ffcc536d6b0, linktarget=0x7ffcc536d6d0)
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/midas.cxx:573
#8  0x000000000041a307 in cm_msg_log (message_type=1, facility=0x46db0e "midas",
    message=0x7e4290 "[mserver,ERROR] [odb.cxx:2498:db_lock_database,ERROR] cannot lock ODB semaphore, 
timeout 10000 ms, exiting...") at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/midas.cxx:685
#9  0x0000000000421fcd in cm_msg_flush_buffer () at /usr/include/c++/11/bits/basic_string.h:194
#10 0x00007fbdeac574dd in __run_exit_handlers () from /lib64/libc.so.6
#11 0x00007fbdeac57620 in exit () from /lib64/libc.so.6
#12 0x0000000000430f7a in db_lock_database (hDB=hDB@entry=1)
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:2499
#13 0x0000000000437e9c in db_find_key (subhKey=0x7ffcc536da04, key_name=0x476a21 "/Alarms/Alarms", hKey=0, 
hDB=1)
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:4099
#14 db_find_key (hDB=1, hKey=hKey@entry=0, key_name=key_name@entry=0x476a21 "/Alarms/Alarms",
    subhKey=subhKey@entry=0x7ffcc536da04) at 
/sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:4075
#15 0x0000000000455fd2 in al_check () at 
/sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/alarm.cxx:614
--Type <RET> for more, q to quit, c to continue without paging--
#16 0x000000000041ff85 in cm_periodic_tasks ()
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/midas.cxx:5596
#17 0x00000000004235c5 in cm_yield (millisec=millisec@entry=1000)
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/midas.cxx:5676
#18 0x00000000004065c2 in main (argc=<optimized out>, argv=0x7ffcc536e628)
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/progs/mserver.cxx:295
(gdb) info thr
  Id   Target Id                          Frame
* 1    Thread 0x7fbdec0b1740 (LWP 601715) 0x00007fbdeaca154c in __pthread_kill_implementation () from 
/lib64/libc.so.6
(gdb) thr 1
[Switching to thread 1 (Thread 0x7fbdec0b1740 (LWP 601715))]
#0  0x00007fbdeaca154c in __pthread_kill_implementation () from /lib64/libc.so.6
(gdb) bt
#0  0x00007fbdeaca154c in __pthread_kill_implementation () from /lib64/libc.so.6
#1  0x00007fbdeac54d06 in raise () from /lib64/libc.so.6
#2  0x00007fbdeac287f3 in abort () from /lib64/libc.so.6
#3  0x0000000000430ee4 in db_lock_database (hDB=hDB@entry=1)
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:2473
#4  0x0000000000437e9c in db_find_key (subhKey=0x7ffcc536d348, key_name=0x4687a8 "/Logger/Message file date 
format",
    hKey=0, hDB=1) at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:4099
#5  db_find_key (hDB=1, hKey=0, key_name=0x4687a8 "/Logger/Message file date format", 
subhKey=0x7ffcc536d348)
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:4075
#6  0x0000000000448297 in db_get_value_string (hdb=1, hKeyRoot=hKeyRoot@entry=0,
    key_name=key_name@entry=0x4687a8 "/Logger/Message file date format", index=index@entry=0,
    s=s@entry=0x7ffcc536d470, create=create@entry=1, create_string_length=0)
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:13950
#7  0x000000000040a690 in cm_msg_get_logfile (fac=<optimized out>, t=<optimized out>, 
filename=0x7ffcc536d690,
    linkname=0x7ffcc536d6b0, linktarget=0x7ffcc536d6d0)
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/midas.cxx:573
#8  0x000000000041a307 in cm_msg_log (message_type=1, facility=0x46db0e "midas",
    message=0x7e4290 "[mserver,ERROR] [odb.cxx:2498:db_lock_database,ERROR] cannot lock ODB semaphore, 
timeout 10000 ms, exiting...") at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/midas.cxx:685
#9  0x0000000000421fcd in cm_msg_flush_buffer () at /usr/include/c++/11/bits/basic_string.h:194
#10 0x00007fbdeac574dd in __run_exit_handlers () from /lib64/libc.so.6
#11 0x00007fbdeac57620 in exit () from /lib64/libc.so.6
#12 0x0000000000430f7a in db_lock_database (hDB=hDB@entry=1)
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:2499
#13 0x0000000000437e9c in db_find_key (subhKey=0x7ffcc536da04, key_name=0x476a21 "/Alarms/Alarms", hKey=0, 
hDB=1)
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:4099
#14 db_find_key (hDB=1, hKey=hKey@entry=0, key_name=key_name@entry=0x476a21 "/Alarms/Alarms",
    subhKey=subhKey@entry=0x7ffcc536da04) at 
/sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:4075
#15 0x0000000000455fd2 in al_check () at 
/sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/alarm.cxx:614
#16 0x000000000041ff85 in cm_periodic_tasks ()
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/midas.cxx:5596
#17 0x00000000004235c5 in cm_yield (millisec=millisec@entry=1000)
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/midas.cxx:5676
#18 0x00000000004065c2 in main (argc=<optimized out>, argv=0x7ffcc536e628)
    at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/progs/mserver.cxx:295
(gdb)

Thank you for the stack trace, I fixed the buglet that cause midas programs to crash twice,
once on failure to lock ODB, then call exit() -> atexit() handlers -> cm_check_connect() -> crash on ODB lock 
failure is the cm_msg() codes.

Replaced exit(1) with abort(). Could have used kill(getpid(),SIGKILL) to avoid making a core dump, but what the 
heck...

Of course this does nothing to the original bug where ODB was locked and nobody will ever unlock it (reboot will 
unlock it!).

commit bdd1d7fdc093b5a8d54a1b8467002bb3cac3ac11

K.O.


> > > I've uploaded the current core dump at: https://gitlab.com/det-lab/coredumps#.
> > 
> > I cannot read the core dump without the corresponding executable (and likely all it's shared libraries).
> > 
> > It is best if you run gdb and extract the stack traces on your end.
> > 
> > In case you are not familiar with gdb:
> > 
> > gdb mserver core # start gdb
> > bt # stack trace of crashed thread
> > info thr # get list of threads
> > thr 1
> > bt
> > thr 2
> > bt
> > # etc, get stack trace of each thread, there should not be too many of them
> > 
> > K.O.
> 
> Hi Konstantin, thanks for the instructions.  I do appear to be missing some debug symbols, but the output 
> looks potentially useful:
> 
> [lekhraj@sdfcdmsdaq ~]$ gdb mserver 
> core.mserver.17468.b174bb74f2bb44f9a0905e78ec6b2677.601715.1728422354000000
> GNU gdb (GDB) Rocky Linux 10.2-11.1.el9_3
> ...
> For help, type "help".
> Type "apropos word" to search for commands related to "word"...
> Reading symbols from mserver...
> [New LWP 601715]
> 
> warning: Section `.reg-xstate/601715' in core file too small.
> [Thread debugging using libthread_db enabled]
> Using host libthread_db library "/lib64/libthread_db.so.1".
> Core was generated by `mserver'.
> Program terminated with signal SIGABRT, Aborted.
> 
> warning: Section `.reg-xstate/601715' in core file too small.
> #0  0x00007fbdeaca154c in __pthread_kill_implementation () from /lib64/libc.so.6
> Missing separate debuginfos, use: dnf debuginfo-install glibc-2.34-83.el9.12.x86_64 libgcc-11.4.1-
> 3.el9.x86_64 libstdc++-11.4.1-2.1.el9.x86_64 libzstd-1.5.1-2.el9.x86_64 mysql-libs-8.0.36-1.el9_3.x86_64 
> openssl-libs-3.0.7-25.el9_3.x86_64 zlib-1.2.11-40.el9.x86_64
> (gdb)
> (gdb) bt
> #0  0x00007fbdeaca154c in __pthread_kill_implementation () from /lib64/libc.so.6
> #1  0x00007fbdeac54d06 in raise () from /lib64/libc.so.6
> #2  0x00007fbdeac287f3 in abort () from /lib64/libc.so.6
> #3  0x0000000000430ee4 in db_lock_database (hDB=hDB@entry=1)
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:2473
> #4  0x0000000000437e9c in db_find_key (subhKey=0x7ffcc536d348, key_name=0x4687a8 "/Logger/Message file date 
> format",
>     hKey=0, hDB=1) at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:4099
> #5  db_find_key (hDB=1, hKey=0, key_name=0x4687a8 "/Logger/Message file date format", 
> subhKey=0x7ffcc536d348)
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:4075
> #6  0x0000000000448297 in db_get_value_string (hdb=1, hKeyRoot=hKeyRoot@entry=0,
>     key_name=key_name@entry=0x4687a8 "/Logger/Message file date format", index=index@entry=0,
>     s=s@entry=0x7ffcc536d470, create=create@entry=1, create_string_length=0)
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:13950
> #7  0x000000000040a690 in cm_msg_get_logfile (fac=<optimized out>, t=<optimized out>, 
> filename=0x7ffcc536d690,
>     linkname=0x7ffcc536d6b0, linktarget=0x7ffcc536d6d0)
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/midas.cxx:573
> #8  0x000000000041a307 in cm_msg_log (message_type=1, facility=0x46db0e "midas",
>     message=0x7e4290 "[mserver,ERROR] [odb.cxx:2498:db_lock_database,ERROR] cannot lock ODB semaphore, 
> timeout 10000 ms, exiting...") at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/midas.cxx:685
> #9  0x0000000000421fcd in cm_msg_flush_buffer () at /usr/include/c++/11/bits/basic_string.h:194
> #10 0x00007fbdeac574dd in __run_exit_handlers () from /lib64/libc.so.6
> #11 0x00007fbdeac57620 in exit () from /lib64/libc.so.6
> #12 0x0000000000430f7a in db_lock_database (hDB=hDB@entry=1)
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:2499
> #13 0x0000000000437e9c in db_find_key (subhKey=0x7ffcc536da04, key_name=0x476a21 "/Alarms/Alarms", hKey=0, 
> hDB=1)
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:4099
> #14 db_find_key (hDB=1, hKey=hKey@entry=0, key_name=key_name@entry=0x476a21 "/Alarms/Alarms",
>     subhKey=subhKey@entry=0x7ffcc536da04) at 
> /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:4075
> #15 0x0000000000455fd2 in al_check () at 
> /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/alarm.cxx:614
> --Type <RET> for more, q to quit, c to continue without paging--
> #16 0x000000000041ff85 in cm_periodic_tasks ()
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/midas.cxx:5596
> #17 0x00000000004235c5 in cm_yield (millisec=millisec@entry=1000)
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/midas.cxx:5676
> #18 0x00000000004065c2 in main (argc=<optimized out>, argv=0x7ffcc536e628)
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/progs/mserver.cxx:295
> (gdb) info thr
>   Id   Target Id                          Frame
> * 1    Thread 0x7fbdec0b1740 (LWP 601715) 0x00007fbdeaca154c in __pthread_kill_implementation () from 
> /lib64/libc.so.6
> (gdb) thr 1
> [Switching to thread 1 (Thread 0x7fbdec0b1740 (LWP 601715))]
> #0  0x00007fbdeaca154c in __pthread_kill_implementation () from /lib64/libc.so.6
> (gdb) bt
> #0  0x00007fbdeaca154c in __pthread_kill_implementation () from /lib64/libc.so.6
> #1  0x00007fbdeac54d06 in raise () from /lib64/libc.so.6
> #2  0x00007fbdeac287f3 in abort () from /lib64/libc.so.6
> #3  0x0000000000430ee4 in db_lock_database (hDB=hDB@entry=1)
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:2473
> #4  0x0000000000437e9c in db_find_key (subhKey=0x7ffcc536d348, key_name=0x4687a8 "/Logger/Message file date 
> format",
>     hKey=0, hDB=1) at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:4099
> #5  db_find_key (hDB=1, hKey=0, key_name=0x4687a8 "/Logger/Message file date format", 
> subhKey=0x7ffcc536d348)
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:4075
> #6  0x0000000000448297 in db_get_value_string (hdb=1, hKeyRoot=hKeyRoot@entry=0,
>     key_name=key_name@entry=0x4687a8 "/Logger/Message file date format", index=index@entry=0,
>     s=s@entry=0x7ffcc536d470, create=create@entry=1, create_string_length=0)
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:13950
> #7  0x000000000040a690 in cm_msg_get_logfile (fac=<optimized out>, t=<optimized out>, 
> filename=0x7ffcc536d690,
>     linkname=0x7ffcc536d6b0, linktarget=0x7ffcc536d6d0)
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/midas.cxx:573
> #8  0x000000000041a307 in cm_msg_log (message_type=1, facility=0x46db0e "midas",
>     message=0x7e4290 "[mserver,ERROR] [odb.cxx:2498:db_lock_database,ERROR] cannot lock ODB semaphore, 
> timeout 10000 ms, exiting...") at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/midas.cxx:685
> #9  0x0000000000421fcd in cm_msg_flush_buffer () at /usr/include/c++/11/bits/basic_string.h:194
> #10 0x00007fbdeac574dd in __run_exit_handlers () from /lib64/libc.so.6
> #11 0x00007fbdeac57620 in exit () from /lib64/libc.so.6
> #12 0x0000000000430f7a in db_lock_database (hDB=hDB@entry=1)
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:2499
> #13 0x0000000000437e9c in db_find_key (subhKey=0x7ffcc536da04, key_name=0x476a21 "/Alarms/Alarms", hKey=0, 
> hDB=1)
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:4099
> #14 db_find_key (hDB=1, hKey=hKey@entry=0, key_name=key_name@entry=0x476a21 "/Alarms/Alarms",
>     subhKey=subhKey@entry=0x7ffcc536da04) at 
> /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/odb.cxx:4075
> #15 0x0000000000455fd2 in al_check () at 
> /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/alarm.cxx:614
> #16 0x000000000041ff85 in cm_periodic_tasks ()
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/midas.cxx:5596
> #17 0x00000000004235c5 in cm_yield (millisec=millisec@entry=1000)
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/src/midas.cxx:5676
> #18 0x00000000004065c2 in main (argc=<optimized out>, argv=0x7ffcc536e628)
>     at /sdf/home/l/lekhraj/packages/SuperCDMS_DAQ/midas_fork/progs/mserver.cxx:295
> (gdb)