Have you tried longer files? Maybe a few 100 MB or so. Maybe a buffer is not flushed correctly at the end of a run.

> Have you tried longer files? Maybe a few 100 MB or so. Maybe a buffer is not flushed correctly at the end of a run.

Yes, I did. This 7 KB of the data bank is about the limit. If we go only 1 KB higher it seems that we save all data. In 
our specific case, this is the number of time bins (256 pixels with 7 time bins results in data loss, with 8 time bins it 
seems to be okay, data type is DWORD). 

Of course, a workaround for us is to save at least 8 time bins and throw 7 of them away later on. Nevertheless, since we 
are only in the commissioning phase now this is okay, I would just like to avoid data loss in the data taking phase of the 
experiment so knowing where the problem origins could help. 

I did another test with another FE running that produces a lot of data. The behavior is the same though. If the bank size 
is less than about 8 KB, the bank is not saved anymore. But probably this is anyway the expected behavior since it is a 
different FE that produces the data. 

So if it is coming from the buffer, is there something I could change to test or solve the problem?

Best, Ivo

> > > Dear all
> > > 
> > > We just started our beam time at ILL and just found yesterday that for certain 
> > > settings of our detector the data is not saved into the .mid files. Running "mdump 
> > > -l 10" online we see the data coming in as they should. Nevertheless, if we run 
> > > "mdump -x runXXXXXX.mid" offline, the data file has no events and the banks are 
> > > missing. Any ideas where the data could go lost?
> > > 
> > > Thanks in advance,
> > > Ivo
> > 
> > Have you checked 
> > 
> > /Logger/Channels/0/Settings/Event ID = -1
> > /Logger/Channels/0/Settings/Trigger mask = -1
> > 
> > If these settings are not -1, they filter the data stream for certain events and trigger 
> > masks.
> > 
> > Stefan
> 
> Good morning Stefan
> 
> Both set to -1. We only have one logging channel. If we run a sequence with a few runs and the 
> same settings, sometimes data is in the .mid file and sometimes it is not.
> 
> Best,
> Ivo 


Hi,

If the online mdump is correct (by default using the -1, -1 filter), the data are in the main SYSTEM buffer. 
Similar to the dump -
The fact that the analyzer doesn't see the banks would indicate a buffer handling issue as mentioned by Stefan.
To confirm, I would check at the end of a run that the sum of the equipment "events sent" matches the logger "Events written".

> Have you tried longer files? Maybe a few 100 MB or so. Maybe a buffer is not flushed correctly at the end of a run.

Hi,

If the online mdump is correct (by default using the -1, -1 filter), the data are in the main SYSTEM buffer. 

by the way, similar to the dump - mdump -x file.mid -m raw -d x will show you the events.

The fact that the analyzer doesn't see the banks would indicate a buffer handling issue as mentioned by Stefan.
To confirm, I would check at the end of a run that the sum of the equipment "events sent" matches the logger "Events written".

I have to reproduce the problem to fix it. Why don't you go and modify midas/examples/experiment/frontend.cxx in such a way that 
it creates exactly the banks you have, just with random data. If you see the same problem, send me your frontend file so that I 
can reproduce it.

> I have to reproduce the problem to fix it. Why don't you go and modify midas/examples/experiment/frontend.cxx in such a way that 
> it creates exactly the banks you have, just with random data. If you see the same problem, send me your frontend file so that I 
> can reproduce it.

It would be good to pin point there the data is lost. This is the sequence:

frontend user code -> mfe.c code -> SYSTEM buffer -> mlogger -> disk

To see if correct data arrives to the SYSTEM buffer, run:
mdump -z SYSTEM

To see if mlogger is receiving events from the SYSTEM buffer, run:
mlogger -v ### mlogger should report all events, history and data

To see if mlogger writes events to disk, examine the disk file (in this case, you already did, data is not there).

I would guess that your data does not make it out from the frontend (mdump shows "nothing"),
if data were to arrive into the SYSTEM buffer, it would make it to disk, unless
mlogger is misconfigured (but you already checked that).

If you have trouble with the frontend framework code, you can try to switch from the mfe.c frontend
to the newer c++ tmfe frontend (see progs/fetest_tmfe.cxx and progs/fetest_tmfe_thread.cxx).

K.O.

> It would be good to pin point there the data is lost. This is the sequence:
> 
> frontend user code -> mfe.c code -> SYSTEM buffer -> mlogger -> disk
> 
> To see if correct data arrives to the SYSTEM buffer, run:
> mdump -z SYSTEM
> 
> To see if mlogger is receiving events from the SYSTEM buffer, run:
> mlogger -v ### mlogger should report all events, history and data
> 
> To see if mlogger writes events to disk, examine the disk file (in this case, you already did, data is not there).
> 
> I would guess that your data does not make it out from the frontend (mdump shows "nothing"),
> if data were to arrive into the SYSTEM buffer, it would make it to disk, unless
> mlogger is misconfigured (but you already checked that).
> 
> If you have trouble with the frontend framework code, you can try to switch from the mfe.c frontend
> to the newer c++ tmfe frontend (see progs/fetest_tmfe.cxx and progs/fetest_tmfe_thread.cxx).
> 
> K.O.

Good evening

I tried to reproduce the behavior in a very simple FE but it did not work out. The next thing for me would be to take the FE that is producing this behavior, replace all the device communication and data with dummies. If the problem is still there I would start to simplify as much as possible. 

Following the inputs of KO, I pin-pointed the data loss. The system buffer still gets the data but the mlogger does not write the data event. Then of course the data is also not anymore present in the data file. Therefore, I checked the logger settings again, Event ID and Trigger Mask still -1. Nothing else, at least from my point of view, that is misconfigured. Nevertheless, if it helps I can send my ODB settings. 

When doing the tests just before I found something else that probably can give a hint to the problem. The data is only lost if the time between two runs is long (a few seconds). As an example: If I run a sequence with a loop and after the FE stops the run the loop ends and the next run is started automatically, then only the first run has no data, which is the one after a longer time of no data taking. When I add a "WAIT Seconds 5" after the run before starting the next, not data is written to the disk for any run. I also found this once when adding a sleep(1) at the end of the FE readout function but back then did not think about it any further. 

Best, Ivo

Hi all,

I've ran into a problem where my experiment gets interrupted with a message from 
the logger saying that my disk is nearly full. This does not make sense to me 
because I have deleted almost all the data files from my data directory. I'm 
guessing that somewhere the ODB perceives that the directory is full when in 
reality its not.

Here is the exact message:

[ODBEdit,INFO] Run #252 stopped

09:22:19 [Logger,TALK] disk nearly full, stopping the run

09:22:19 [Logger,ERROR] [mlogger.cxx:4475:log_write,ERROR] Disk '/home/caendaq/A       
NIS/data/run00252.mid.lz4' is almost full: 81 MiBytes free out of 922497 MiBytes       
, stopping the run

Does any body have a solution for this? Thanks so much.

Isaac

The logger simple requests the disk free space level from the operating system in the same 
way as the "df" command does. Can you do a "df" on your system? I have seen that some file 
systems free up space not immediately if you delete files, but some times later (like 24h).

Stefan

> The logger simple requests the disk free space level from the operating system in the same 
> way as the "df" command does. Can you do a "df" on your system? I have seen that some file 
> systems free up space not immediately if you delete files, but some times later (like 24h).
> 
> Stefan

Thanks Stefan. Yes the files were still held open by some processes. It's solved now.

Cheers.

Isaac

there is a problem with mlogger between commits xxx (17 Nov 2020) and a762bb8 (12 feb 2021). because of 
confusion between seconds and milliseconds, FILE (mhf*.dat files) and SQL history are recording with 
incorrect timestamps.

- traditional MIDAS history (*.hst files) does not have this problem (because of a buglet)
- midas-2020-12 release does not have this problem (it has mlogger from midas-2020-08 release)

there are some additional changes in mlogger that we are sorting out, when ready, we will make a new 
release of midas.

K.O.

Hello!
Sometimes when I mess around with the history plots I get the following error:

[mhttpd,ERROR] [history.cxx:97:xread,ERROR] Error: Unexpected end-of-file when 
reading file "/home/wagasci-ana/Data/online/210219.hst"

I have tried the following without success:

- Remove the MIDAS history files
- Restart mhttpd and mlogger

I do not know what triggers the error but when it triggers the above message is 
printed hundres of times a second, completely spamming the message log.

It happened again today after I set the label of a frontend too long making 
mlogger crash. After fixing the label length, the above message appeared and it 
does not seem to go away.

It appears that the issue is trigger by a nonexisting Event and Variable as shown 
in the attached picture. This issue can arise when restoring the ODB from a 
previous version or importing ODB values from other MIDAS instances.
It might be useful if the error message were more clear about the source of the 
problem.

> Hello!
> Sometimes when I mess around with the history plots I get the following error:
> 
> [mhttpd,ERROR] [history.cxx:97:xread,ERROR] Error: Unexpected end-of-file when 
> reading file "/home/wagasci-ana/Data/online/210219.hst"
> 
> I have tried the following without success:
> 
> - Remove the MIDAS history files
> - Restart mhttpd and mlogger
> 
> I do not know what triggers the error but when it triggers the above message is 
> printed hundres of times a second, completely spamming the message log.
> 
> It happened again today after I set the label of a frontend too long making 
> mlogger crash. After fixing the label length, the above message appeared and it 
> does not seem to go away.

I have a history that is embedded in a custom page using

<div class="mjshistory" data-group="SampleCryo" data-panel="SampleTemp" data-scale="30m" style="'+size+' position: relative;left: 640px;top: -205px;"></div>

this works fine when I load the page but seems to cause a timeout when reloading (F5) the page. It used to work fine last year but since a midas update this year it does not work. 

When I manually stop the script when firefox reports that it is slowing down the browse I get the following in the console:

Script terminated by timeout at:
binarySearch@http://xxx.psi.ch:8081/mhistory.js:1051:11
MhistoryGraph.prototype.findMinMax@http://xxx.psi.ch:8081/mhistory.js:1583:28
MhistoryGraph.prototype.loadInitialData/<@http://xxx.psi.ch:8081/mhistory.js:780:15

any ideas what may be causing this?

thanks.

Another hint to the problem, the custom page is accessible via 
http://xxx.psi.ch:8081/?cmd=custom&page=SampleCryo&
once loaded the address changes to where A and B change values as time passes (I guess B-A=30m).
http://xxx.psi.ch:8081/?cmd=custom&page=SampleCryo&&A=1614173369&B=1614175169

I have to reproduce the problem. Can you please send me the full link by direct email. As you know, I'm also at PSI.

Stefan

Hi all,

I'm currently experiencing an issue during run transitions. It comes in the form 
of an alert saying "TypeError: Cannot read property 'length' of undefined" 
whenever I'm in the "transition" window on mhttpd. I have attached an image of 
what the transition window looks like when this happens. 

By the looks of it and by peering at the lines in transition.html where the 
error occurs, it's pretty obvious that there is some strange undefined client 
that the web page tries to access.

I don't know how to find what this client is. Is there a way to see it in the 
ODB? 

The issues happens in show_client() of transition.html (called by callback()). 
Here's the trace:

Uncaught (in promise) TypeError: Cannot read property 'length' of undefined
    at show_client (?cmd=Transition:227)
    at callback (?cmd=Transition:420)
    at ?cmd=Transition:430

Any help would be very appreciated!

Thanks so much.

Isaac

The most recent commit (b43aef648c2f8a7e710a327d0b322751ae44afea) throws this 
compiler error:
src/tmfe_main.cxx:39:11: error: 'SIGPIPE' was not declared in this scope
    signal(SIGPIPE, SIG_IGN);

It's fixed by adding #include <signal.h> to that file.

> The most recent commit (b43aef648c2f8a7e710a327d0b322751ae44afea) throws this 
> compiler error:
> src/tmfe_main.cxx:39:11: error: 'SIGPIPE' was not declared in this scope
>     signal(SIGPIPE, SIG_IGN);
> 
> It's fixed by adding #include <signal.h> to that file.

"but it works just fine on my mac!"

anyhow, thank you for reporting this problem, it already fixed. the bitbucket auto-
build also caught it. I also boogered up "make remoteonly", also fixed now.

BTW, for production use I recommend midas from the "release" branches, unless one 
needs a bug fix or new feature from the development branch.

K.O.

Clearly something goes wrong with the STARTABORT transition. Actually from your 
sceenshot, it is not clear why the STARTABORT transition was initiated.

Usually it is called after some client fails the "start run" transition to inform 
other clients that the run did not start after all. (mlogger uses this to close the 
output file, etc).

But in the screenshot, we do not see any client fail the transition (only rootana1 
was called, and it returned "green").

So, a puzzle. One possibility is that the transition code gets so confused
that it does not record correct transition data to ODB, then the web page
gets even more confused.

One way to see what happens, is to run the odbedit command "start now -v".

Can you try that? And attach all it's output here?

K.O.

> > [mhttpd,ERROR] [history.cxx:97:xread,ERROR] Error: Unexpected end-of-file when 
> > reading file "/home/wagasci-ana/Data/online/210219.hst"

I am puzzled. We can try two things:

a) look inside the "bad" hst file, maybe we can see something. run "mhdump -L 
/home/wagasci-ana/Data/online/210219.hst". If there is anything wrong with the file, it 
will be probably at the end. You can also try to run it without "-L".

b) switch from "midas" history (.hst files) to "FILE" history (mh*.dat files), the 
"FILE" history code is newer and the file format is more robust, with luck it may 
survive whatever trouble is happening in your experiment. This is controlled in ODB 
/Logger/History/XXX/Active (set to "y/n").

c) the output of "mlogger -v" may give us some clue, it usually complains if something 
is not right with definitions of history data.

K.O.