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ID Date Authorup Topic Subject
  2445   29 Oct 2022 Stefan RittSuggestionread_only odbxx?
Ok, I implemented and committed that. Just call


on a key you don't want to modify. If you do so, an exception gets thrown.

  2448   12 Nov 2022 Stefan RittBug FixO_CREAT in open in split.cxx
> midas currently does not compile on linux
> /usr/include/x86_64-linux-gnu/bits/fcntl2.h:50:24: error: call to Ď__open_missing_modeí declared with attribute error: open with O_CREAT or O_TMPFILE in second argument needs 3 arguments
>    50 |    __open_missing_mode ();
> giving the mode is mandatory:
> fix is to give open in midas/examples/lowlevel/split.cxx a default mode, e.g. 006600

Thanks. Fixed.

  2452   13 Jan 2023 Stefan RittSuggestionDebug printf remaining in mhttpd.cxx
These debug statements were added by K.O. on June 24, 2021. He should remove it.

  2454   31 Jan 2023 Stefan RittSuggestion"Soft interlock" possible?
> Is it possible to impose requirements on certain output variables in an interlock-like fashion? For example: "As long as the temperature exceeds a certain threshold, a light switched by a relay cannot be turned on."
> A workaround would be to set an alarm on that variable and call a script which turns the light back off, but that might not be ideal in certain scenarios. For safety-critical situations, a PLC would be preferred, but I am missing an option between those two.

No, interlocks of that kind are not implemented in midas. And that is for a good reason. Interlocks are critical, so one must be sure 100% that they are working. This cannot be done with complex software such as midas. You have to use dedicated hardware for that. 
Most people use a PLC controller which is made for that. Midas is then only used to read and display the status of the interlock controller.

  2455   08 Feb 2023 Stefan RittSuggestionhistories capture 'ruy'
> The histories capture key events from 'r' 'u' 'y' and 'Escape' for various functions like rescaling etc. However, this also means that if we include an editable modbvalue and a history in the same custom page then changing the modbvalue to something that includes 'ruy' is not possible.
> In mhistory.js we have
> // Keyboard event handler (has to be on the window!)
> window.addEventListener("keydown", this.keyDown.bind(this));
> I am not sure why it "has to be on the window". For now, I am bypassing this issue by changing the event listener to "keyup" but maybe there is a more elegant solution for this. Adding the event listener to the div element that includes the history does not seem to work.

I could reproduce the problem. I see two options there:

1) We replace 'r' with 'Ctrl-r' etc. 

2) We change the history JS code not to process keyboard inputs if we are currently editing a value.

I added 2) to give it a try. It works fine for me. The additional code is

MhistoryGraph.prototype.keyDown = function (e) {
   // don't consume events if we are editing a value
   if ( === "INPUT")

Feedback is welcome.

  2457   09 Feb 2023 Stefan RittSuggestionhistories capture 'ruy'
> I agree with you, option 2 is better and works well. 
> The only problem is that if you are showing multiple histograms in the same window the keyDown even will affect all of the histories in the window. 
> This may be the intended behaviour, but I think that if we can find a way to have the event affecting only the intended history (focused element for example) it would be better.

The history panels are simple pictures from the perspective of the browser and have no concept of a focus. This would have to be tweaked somehow. If you want to reset a single history, 
just click on its reset button (circle arrow at the right top).

  2459   22 Feb 2023 Stefan RittInfoconnection to a MySQL server: retry procedure in the Logger
> Dear all,
> we are experiencing a connection problem to the MySQL server that we use to log informations. Is there an 
> option to retry multiple times the I/O on the MySQL?
> The error we are experiencing is the following (hiding the IP address):
> [Logger,ERROR] [mlogger.cxx:2455:write_runlog_sql,ERROR] Failed to connect to database: Error: Can't 
> connect to MySQL server on '' (110)
> Then the logger stops, and must be restarted. This eventually happens only during the BOR or the EOR.

What would you propose? If the connection does not work, most likely the server is down or busy. If we retry, 
the connection still might not work. If we retry many times, people will complain that the run start or stop 
takes very long. If we then just continue (without stopping the logger), the MySQL database will miss important 
information and the runs probably cannot be analyzed later. So I believe it's better to really stop the logger 
so that people get aware that there is a problem and fix the source, rather than curing the symptoms.

In the MEG experiment at PSI we run the logger with a MySQL database and we never see any connection issue, 
except when the MySQL server gets in maintenance (once a year), but usually we don't take data then. Since we 
use the same logger code, it cannot be a problem there. So I would try to fix the problem on the MySQL side.

  2483   27 Apr 2023 Stefan RittSuggestionMaximum ODB size
> Congratulations. created != "it works".

Two other tings to consider:

1) The ODB shared memory is dumped into a binary file (".ODB.SHM") after the last client finished and read if the first client starts, to get it persistent. 
So this could slow down starting and stopping, but only the first client, so I guess it's not an issue.

2) Traditionally, the ODB gets dumped to the .mid file at the beginning and end of every run, so that one know the exact configuration of the experiment
for offline analysis. This can be turned off of course, but most experiments use it. If the ODB is dumped in any ASCII format, this can take quite long.
Assume it takes 10 seconds at the beginning of each run, and we take a run every five minutes. Then we loose 48 mins of precious beam time every day.

  2486   28 Apr 2023 Stefan RittSuggestionMaximum ODB size
> Is this maybe related to what Stefan said about the run start - so that odbedit needs some time to load the bigger ODB?

At the run start mlogger writes the ODB to the .mid file. This needs conversion (binary ODB -> XML ASCII) which can take time.
This does NOT depend on the ODB size, but on the ODB *content*. Every key in the ODB takes time to convert. So if your ODB as 1.5 GB
but only a few keys, this is still fast. Only if you have 200 million keys int he ODB, then mlogger takes lots of time to convert
200 million values to XML or JSON strings.

  2502   02 May 2023 Stefan RittForumProblem with running midas odbxx frontends on a remote machine using the -h option

>  Shall I create a pull request for the additional RPC argument or will you just fix this on the fly?

Just fix it in the fly yourself. Itís an obvious bug, so please commit to develop.

  2504   08 May 2023 Stefan RittForumScrript in sequencer
> I tried different ways to pass parameters to bash script, but there are seems to 
> be empty, what could be the problem?

Indeed there was a bug in the sequencer with parameter passing to scripts. I fixed it
and committed the changes to the develop branch.

  2506   10 May 2023 Stefan RittForumScrript in sequencer
> Thanks. It works perfect.
> Another question is:
> Is it possible to run .msl seqscript from bash cmd?
> Maybe it's easier then
> 1 odbedit -c 'set "/sequencer/load filename" filename.msl'
> 2 odbedit -c 'set "/sequencer/load new file" TRUE'
> 3 odbedit -c 'set "/sequencer/start script" TRUE'

That will work.

> What is the best way to have a button starting sequencer
> from  /script (or /alias )?

Have a look at

where I put the necessary information.

  2509   10 May 2023 Stefan RittSuggestionMake sequencer more compatible with mobile devices

Lukas Gerritzen wrote:
When trying to select a run script on an iPad or other mobile device, you cannot enter subdirectories. This is caused by the following part:

We are working right now on a general file picker, which will replace also the file picker for the sequencer. So please wait until the new thing is out and then test it there.

  2510   10 May 2023 Stefan RittSuggestionDesktop notifications for messages

Lukas Gerritzen wrote:
It would be nice to have MIDAS notifications pop up outside of the browser window.

There are certainly dozens of people who do "I don't like pop-up windows all the time". So this has to come with a switch in the config page to turn it off. If there is a switch "allow pop-up windows", then we have the other fraction of people using Edge/Chrome/Safari/Opera saying "it's not working on my specific browser on version x.y.z". So I'm only willing to add that feature if we are sure it's a standard things working in most environments.

  2513   11 May 2023 Stefan RittSuggestionDesktop notifications for messages
Ok, I implemented desktop notifications. In the MIDAS config page, you can now enable browser notifications for the different types of messages. Not sure this works perfectly, but a staring point. So please let me know if there is any issue.

  2514   12 May 2023 Stefan RittInfoNew environment variable MIDAS_EXPNAME
A new environment variable MIDAS_EXPNAME has been introduced. This must be
used for cases where people use MIDAS_DIR, and is then equivalent for the
experiment name and directory usually used in the exptab file. This fixes
and issue with creating and deleting shared memory in midas as described in

The documentation has been updated at

  2518   16 May 2023 Stefan RittBug Reportexcessive logging of http requests
Maybe you remember the problems we had with a custom page in Japan loading it from TRIUMF. It took almost one minute since each RPC request took 
about 1s round-trip. This got fixed by the modb* scheme where the framework actually collects all ODB variables in a custom page and puts them 
into ONE rpc request (making the path an actual array of paths). That reduced the requests from 100 to 1 in the above example. Maybe the same 
could be done in your current case. Pulling one ODB variable at a time is not very efficient.

  2527   12 Jun 2023 Stefan RittSuggestionMaximum ODB size
> correction: ODB shared memory is saved to .ODB.SHM each time a client stops, this is db_close_database().

The original design of the midas shared memory (back in the 1990's) was that the ODB shared memory file gets
only saved into the .ODB.SHM when the *last* client exits. This ensures to keep the ODB persistent when the
shared memory gets deleted. I vaguely remember I put something in like:

  destroy_flag = (pheader->num_clients == 0);

  if (destroy_flag)
     ss_shm_flush(pheader->name, pdb->shm_adr, pdb->shm_size, pdb->shm_handle);

Now I see that the "if (destory_flag)" is missing. Not sure if it was removed once, or if it actually never
was there. But I see no point in flushing the ODB when a client ends. We need the flushing only before the
shared memory gets deleted. We we have to ensure that the share memory and the binary dump file stay in sync
(like if all midas clients die at the same time), we could add some code to flush the ODB like once per minute,
but not attach it to db_close_database(). I know several experiments using "odbedit -c xxx" in vast quantities,
so all these experiments would then benefit.

Note: Mu3e at PSI also uses 100 MB ODB, and they really need it.

Thoughts and opinions?

  2529   13 Jun 2023 Stefan RittSuggestionMaximum ODB size
> I remember the same, but I tracked it down in git to the very first commit, and there is no if() there,
> odb is saved to .ODB.SHM on every client shutdown, not just the last client. I guess we both misremebered.

I confirm. Really strange how your mind can trick you. I'm absolutely sure I had this planned originally (1995?), but it got never implemented.

Well, never too late. So I added the "if" and committed to develop. I did a quick test and things seem to work fine here. Actually programs stop 
a bit faster now. So please everybody give it a try and report back here.

BTW, how do I resize the ODB. I remember we discussed this some time ago, and concluded that odbedit needs a resize flag. Has this even been 
done? If not, what is the "official" way to resize the ODB. We had some documentation about that some time ago, but I can't find it anymore.

  2532   13 Jun 2023 Stefan RittForumInclude subroutine through relative path in sequencer
> Hi, I would like to restructure our sequencer scripts and the paths. Until now many things are not generic at all. I would like to ask if it is possible to include files through a relative path for example something like 
> INCLUDE ../chip/global_basic_functions
> Maybe I just did not found how to do it.

It was not there. I implemented it in the last commit.

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