Thanks for the detailed report. Let me reply one-by-one.

> 1) history plots on 12 hrs, 24 hrs tend to hang with "page not responsive". most plots have 16-20 variables, 
> which are recorded at 1/sec interval. (yes, we must see all the variables at the same time and yes, we want to 
> record them with fine granularity).

Attached is a similar plot. 8 values recorded every second, displayed for 24h. The backend is actually a Raspberry Pi! I see no issues there. Do you have 
the current history version which does the re-binning? Actually the plot below is still without rebinding (see the "1" at the top right), and it contains ~72000 points x 8. The browser does not have any issue 
with it.

Stefan

> 3) ODB editor clicking on hex number versus decimal number no longer allows editing in hex, Stefan implemented 
> this useful feature and it worked for a while, but now seems broken.

I cannot confirm. See below. There was some issue some time ago, but that's fixed since a while. Please pull on develop and try again.

Here is the change: https://bitbucket.org/tmidas/midas/commits/882974260876529c43811c63a16b4a32395d416a

Stefan

> 4) ODB editor "right click" to "delete" or "rename" key does not work, the right-click menu disappears 
> immediately before I can use it (dl-server-2), click on item (it is now blue), right-click menu disappears 
> before I can use it (daq17). it looks like a timing or race condition.

Confirmed and fixed: https://bitbucket.org/tmidas/midas/commits/4ba30761683ac9aa558471d2d2d35ce05e72096a

/Stefan

> 5) ODB editor "create link" link target name is limited to 32 bytes, links cannot be created (dl-server-2), ok 
> on daq17 with current MIDAS.

Works for me with the current version.


> 6) MIDAS on dl-server-2 is "installed" in such a way that there is no connection to the git repository, no way 
> to tell what git checkout it corresponds to. Help page just says "branch master", git-revision.h is empty. We 
> should discourage such use of MIDAS and promote our "normal way" where for all MIDAS binary programs we know 
> what source code and what git commit was used to build them.

Not sure if you have seen it. I make a "install" script to clone, compile and install midas. Some people use this already. Maybe give it a shot. Might need 
adjustment for different systems, I certainly haven't covered all corner cases. But on a RaspberryPi it's then just one command to install midas, modify 
the environment, install mhttpd as a service and load the ODB defaults. I know that some people want it "their way" and that's ok, but for the novice user 
that might be a good starting point. It's documented here: https://daq00.triumf.ca/MidasWiki/index.php/Install_Script

The install script is plain shell, so should be easy to be understandable. 

> 6a) MIDAS on dl-server-2 had a pretty much non-functional history display, I reported it here, Stefan provided 
> a fix, I manually retrofitted it into dl-server-2 MIDAS and we were able to run the experiment. (good)
> 
> 6b) bug (5) suggests that there is more bugs being introduced and fixed without any notice to other midas 
> users (via this forum or via the bitbucket bug tracker).

If I would notify everybody about a new bug I introduced, I would know that it's a bug and I would not introduce it ;-)

For all the fixes I encourage people to check the commit log. Doing an elog entry for every bug fix would be considered spam by many people because 
that can be many emails per week. The commit log is here: https://bitbucket.org/tmidas/midas/commits/branch/develop

If somebody volunteers to consolidate all commits and make a monthly digest to be posted here, I'm all in favor, but I'm not that individual.

Stefan

Now I had a similar case that the browser froze when showing 24h of data. Tuned out that 80k points are a bit much. I changed the code so that it starts binning when showing 8h or more. This is not a perfect solution. The code should check at which interval data is written, then 
automatically start binning when approaching 4000 points or more. That would however require more complicated code, so I leave it as it is right now. Feedback welcome.

Stefan

I wonder why one needs more than 256 hotlinks at all. Please note that with the odbxx "watch" API, you can hotline a whole subdirectory, and get notified if ANY of the 
underlying values or subdirectories change. In principle, one could have one hotlink to "/" and see all changes in the ODB (although that does not make sense and might slow 
down ODB access a bit).

Try the odbxx_test.cpp example in MIDAS. In line 210 it puts a single hotlink to /Experiment. If you change anything under /Experiment, the program gets notified. By checking the 
path of the changed ODB entry, it can figure out which of the subways have been changed:

   // watch ODB key for any change with lambda function
   midas::odb ow("/Experiment");
   ow.watch([](midas::odb &o) {
      std::cout << "Value of key \"" + o.get_full_path() + "\" changed to " << o << std::endl;
   });


Maybe that would solve your problem without having to change the maximum number of hotlinks.

Stefan

> Dear all, I implemented an optional timeout for the wait ODBvalue command. The way it works is similar to the standard wait command:
> 
> WAIT ODBvalue, /Equipment/HV/Variables/Measured[3], <, 100, timeout, 60
> 
> where the "timeout" keyword start a countdown in seconds. If the ODB condition is not met after 60 seconds the sequencer moves on to the next line.
> 
> To use this feature you must recompile the msequencer, delete /Sequencer/State and start the freshly compiled msequencer. This will add two ODBs to the /Sequencer/State: "Timeout value" (the countdown) and "Timeout limit" (the limit given in the wait command).
> 
> I suggest that we add something similar to the pysequencer using the same ODBs.

How can the MSL code figure out if the wait succeeded or timed out?

Stefan

> > 
> > How can the MSL code figure out if the wait succeeded or timed out?
> > 
> > Stefan
> 
> You get a message, something like:
> 17:52:12.293 2026/05/29 [Sequencer,INFO] WAIT ODBValue timeout after 10.0 seconds: /Equipment/Test/Variables/V < 1 not satisfied
> 
> Do we need something else?
> 
> Zaher

I mean how can the following code determine the timeout?

> > > > 
> > > > How can the MSL code figure out if the wait succeeded or timed out?
> > > > 
> > > > Stefan
> > > 
> > > You get a message, something like:
> > > 17:52:12.293 2026/05/29 [Sequencer,INFO] WAIT ODBValue timeout after 10.0 seconds: /Equipment/Test/Variables/V < 1 not satisfied
> > > 
> > > Do we need something else?
> > > 
> > > Zaher
> > 
> > I mean how can the following code determine the timeout?
> 
> My intention with this was dealing with something like setting a cryostat temperature or any non-critical parameter. If it is not reached within a given timeout we give up and move on with the plan rather than sitting and wasting a whole night of beam. If your ODBvalue is "mission critical" then the wait command should not be used with a timeout. If you do use the timeout option then you will have to check in the following lines what is the state of your ODBvalue (very easy). To me this is the simplest and most useful way for our use case.

I was more thinking like a return value 0/1 if the wait function. If you change the condition, you only have to change it in one location. More like normal C functions work.

Stefan 

Dear all,

I want to control (start / stop / monitor its stdout and stderr) an external process (systemd / EPICS IOC shell script) from within MIDAS.

In order to make this as convenient as possible for the user, I want the process to behave just like any other MIDAS client:
- I can start it from the ODB as a program
- The process gets regularly polled from MIDAS to see whether it is still running
- I can stop the process from the ODB like any other program
- Optional, but highly appreciated: Its stdout and stderr should be a MIDAS message.

Did anyone already solve a similar problem?

Best regards
Stefan

Thanks a lot,

Nick. Regarding the messages: Zaher showed me that it is possible to simply place a custom log file generated by the systemd next to midas.log - then it shows up next to the "midas" tab in "Messages".

One follow-up question: Is it possible to use the systemctl status for the "Running on host" column? Or does this even happen automatically?

Best regards
Stefan

> Hi,
> 
> what you describe is exactly how I normally run mhttpd, mlogger, mserver and some other
> custom frontend programs. Eg:
> 
> [local:T2KGSC:Running]/>ls /programs/Logger/
> Required                        y
> Watchdog timeout                100000
> Check interval                  180000
> Start command                   systemctl --user start mlogger
> Auto start                      n
> Auto stop                       n
> Auto restart                    n
> Alarm class                     AlarmNotify
> First failed                    0
> 
> The only exception is your last point about stdout and stderr
> being midas messages. I use journalctl to see these.
> 
> Cheers,
> 
> Nick.
> 
> > I want to control (start / stop / monitor its stdout and stderr) an external process (systemd / EPICS IOC shell script) from within MIDAS.
> > 
> > In order to make this as convenient as possible for the user, I want the process to behave just like any other MIDAS client:
> > - I can start it from the ODB as a program
> > - The process gets regularly polled from MIDAS to see whether it is still running
> > - I can stop the process from the ODB like any other program
> > - Optional, but highly appreciated: Its stdout and stderr should be a MIDAS message.
> > 
> > Did anyone already solve a similar problem?
> > 
> > Best regards
> > Stefan

Hi,

unfortunately I don't have a documentation link to the feature, I just know that it works on my machine ;-) The general idea is that you place a custom whatever.log file in Logger/Data Dir (where midas.log is stored). Then, in the Messages page, there will be a "midas" tab and a "whatever" tab - the latter showing the content of whatever.log. One problem here is that timestamping does not work automatically - you have to prepend every line with the same Hours:Minutes:Seconds.Milliseconds Year/Month/Day format that midas.log is using.

So you have a custom Programs page which does systemctl status on your systemd? Does the status then transfer over automatically to the Status page? Is there an example how to write such a custom page?

Best regards
Stefan

> Hi,
>  
> > Nick. Regarding the messages: Zaher showed me that it is possible to simply place
> > a custom log file generated by the systemd next to midas.log - then it shows up
> > next to the "midas" tab in "Messages".
> 
> Interesting. I'm not familiar with that feature. Do you have link to documentation?
> 
> > One follow-up question: Is it possible to use the systemctl status for the
> > "Running on host" column? Or does this even happen automatically?
> 
> On the programs page that column is populated by the odb key /System/Clients/<PID>/Host
> so no. However, there is nothing stopping you from writing your own version of
> programs.html to show whatever you want. For example I have a custom programs
> page the includes columns to enable/disable and to reset watchdog alarms.
> 
> Cheers,
> 
> Nick.

Hello!

My name is Soichiro Kuribayashi and I am a Ph.D. student at Kyoto University. 
I'm a T2K collaborator and working for Super FGD which is new detector in ND280.

I'm a beginner of MIDAS and I've just started to develop the DAQ software with 
MIDAS for Super FGD.
For the DAQ of Super FGD, we will run remotely front end part of MIDAS on ZYNQ 
which is system on chip.

For this remote control of front end part with mserver, we have to mount home 
directory of DAQ PC(Cent OS8) on that of Linux on ZYNQ.
So I wonder if we should use NFS(Network file system) + NIS(Network information 
service) + autofs for the mounting. Is it correct?

If you have any information or any suggestion for the remote control on chip, 
please let me know.

Best regards,
Soichiro 

Dear Konstantin,

Thank you very much for your reply and detailed information.
I would appreciate if you could help us.

> I can also suggest that on your frontend SOC/FPGA machine, you boot linux
> using the "nfs-root" method. This way, the local flash memory only
> contains a boot loader (and maybe the linux kernel image, depending on
> bootloader limitations). The rest of the linux rootfs can be on your
> central development machine. This way management of flash cards,
> confusion with different contents of local flash and need to make backups
> of frontend machines is much reduced.

As you said, we can run complete Linux (Ubuntu 16) on ZYNQ and I'm using common NFS 
system now. However, I didn't know "nfs-root" method which you mentioned and this method 
seems to be reasonable way to just share linux rootfs.
First of all, I will try this method for simpler system.

> If you use a fast SSD and ZFS with deduplication, you will also have good
> performance gain (NFS over 1gige network to server with fast SSD works
> so much better compared to the very slow SD/MMC/NAND flash).
>
> I can point you to some of my documentation how we do this.

I'm concerned about such performance and I have checked the performance with common NFS 
over gige network and my DAQ PC roughly(data transfer rate ~ O(10) MByte/sec). However, I 
didn't know the ZFS and also how we can have performance gain with a fast SSD and ZFS.
Please let me know your documentation how to do it if possible.

> I would say you are on a good track. For early development on just one board,
> pretty much any way you do it will work, but once you start scaling up
> beyound 3-4-5 frontends, you will start seeing benefits from common NFS-mounted
> home directories, NFS-root booted linux, etc.

I'm developing with just one board and common NFS-mounted now. I'm looking forward to 
seeing such benefits when I will use multiple frontends.
 
> And of course you may want to study the existing ND280/FGD DAQ. I hope you
> have access to the running system at Jparc. If not, I have a copy of
> pretty much everything (except for running hardware, it is stored in the basement, 
> dead) and I can give you access.

I don't have access to the system at Jparc, but Nick has told us where FGD DAQ code is.
Is bellow URL everything of code of FGD DAQ?
https://git.t2k.org/hastings/fgddaq/-/tree/master

Best regards,
Soichiro

Dear Stefan,

Thank you very much for your help.

I have already contacted someone who has used ZYNQ in that order and It's working fine for now.
But, I'll let you know if something goes wrong.

Best regards,
Soichiro