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.

> 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 its output here?
> 
> K.O.

Thanks for getting back to me right away. I've attached two screenshots. The first one 
is the output after running "start now -v" (everything seemed to work nicely there), the 
second output is after using odbedit to stop the run with "stop". Notice that the DAQ 
never stops because it gets stuck in between transitions (You can see the run status 
being "stopping run" with the cancel transition button).

Thanks.

Isaac

So there is no error on run start anymore? To debug the stuck run stop, please use "stop -v" 
to see where it got stuck. You can also play with the RPC timeouts (the connect timeout and 
the response timeout), to make it get "unstuck" quicker. Definitely it should not be stuck 
forever, it should timeout at maximum of "rpc timeout * number of clients". K.O.

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

Fair point. I would suggest adding that recommendation to the wiki instructions. I 
forget to add that step otherwise.

> So there is no error on run start anymore? To debug the stuck run stop, please use "stop -v" 
> to see where it got stuck. You can also play with the RPC timeouts (the connect timeout and 
> the response timeout), to make it get "unstuck" quicker. Definitely it should not be stuck 
> forever, it should timeout at maximum of "rpc timeout * number of clients". K.O.

You're right it does not stay stuck forever, it eventually gets unstuck. I forgot to mention this. 
I will try to play with these timeout parameters. It does not get stuck if I run my DAQ using the 
odbedit commands (start/stop). I don't know if this is relevant information that could help us 
identify the problem.

Thanks for all your help as always!

Isaac

> It does not get stuck if I run my DAQ using the odbedit commands (start/stop).

Interesting. Run start/stop from odbedit works but from mhttpd gets stuck.

I think they do not run the transition quite the same way. mhttpd uses the multithreaded transition.

So we can debug this using the "mtransition" program. Try:

- mtransition -v -d 1 START/STOP -- this should be same as odbedit
- mtransition -m -v -d 1 START/STOP -- this should be same as mhttpd

The "-v" and "-d 1" flags should cause lots of output, for failed transitions,
cut-and-paste it all into this elog here, should give us plenty of meat to debug.

K.O.

Hello!

Could you help me solve the problem of compatibility between our frontend (created in 2017) and the fresh MIDAS? The old MIDAS (2017) worked well, then we did not use it.
While compiling the frontend, I get a lot of warnings and a few compilation errors.

Any help will be greatly appreciated.

Thanks in advance.
With the best regards,
Svetlana

Version: release/midas-2020-12

I'm exporting the history data shown in elog:2132/1 to CSV, but when I look at the 
CSV data, the step no longer occurs at the same time in both data sets (elog:2132/2)

History is from two separate equipments/frontends, but both have "Log history" set to 1.

Tried with export of two different time ranges, and the shift appears to remain the same, 
about 4040 rows.

I confirm there is a problem. If variables are from the same equipment, they have the same 
time stamps, like

t1 v1(t1) v2(t1)
t2 v1(t2) v2(t2)
t3 v1(t3) v2(t3)

when they are from different equipments, they have however different time stamps

t1 v1(t1)
t2    v2(t2)
t3 v1(t3)
t4    v2(t4)

The bug in the current code is that all variables use the time stamps of the first variable, 
which is wrong in the case of different equipments, like

t1 v1(t1) v2(*t2*)
t3 v1(t3) v2(*t4*)

So I can change the code, but I'm not sure what would be the bast way. The easiest would be to 
export one array per variable, like

t1 v1(t1)
t2 v1(t2)
...
t3 v2(t3)
t4 v2(t4)
...

Putting that into a single array would leave gaps, like

t1 v1(t1) [gap]
t2 [gap]  v2(t2)
t3 v1(t3) [gap]
t4 [ga]]  v2(t4)

plus this is programmatically more complicated, since I have to merge two arrays. So which 
export format would you prefer?

Stefan

I think from my perspective the separate files are fine. I personally don't really like the format 
with the gaps, so don't see an advantage in putting in the extra work.
I'm surprised the shift is this big, though, it was more than a whole hour in my case, is it the 
time difference between when the frontends were started?

Version: release/midas-2020-12

In the new history display, the checkbox "Change all time axes together" works 
well with the mouse-based zoom, but does not apply to the +- buttons.

I finally found some time to fix this issue in the latest commit. Please update and check if it's 
working for you.

Stefan

> Version: release/midas-2020-12
> 
> In the new history display, the checkbox "Change all time axes together" works 
> well with the mouse-based zoom, but does not apply to the +- buttons.

Fixed in current commit.

Stefan

It seems that a modbselect triggers a "change" in an ODB which has a hot link. This happens onload (or whenever the custom page is reloaded) and otherwise it behaves as expected, i.e. no change unless the modbselect is actually changed. Is this the intended behaviour? can this be modified?