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    Reply  05 Nov 2020, Pierre-Andre Amaudruz, Forum, Building an experiment using CAEN VME interface - unknown type name 'VARIANT_BOOL' 
Hi,

You're building under Linux like. You want to define the LINUX and skip the VARIANT_BOOL all together.
PAA

> Hi everyone,
> 
> I have been building an experiment using the v1718 CAEN interface to talk to my modules and I am using the CAENVMElib Linux Library (2.50). I've managed to deal with data type issues by including additional libraries to my driver code but there is one type error 
that persists:
> 
> 
> In file included from /usr/include/CAENVMElib.h:27:0,
>              	from include/v1718.h:25,
>              	from v1718.c:26:
> /usr/include/CAENVMEtypes.h:323:9: error: unknown type name ‘VARIANT_BOOL’
>      	CAEN_BOOL cvDS0;  	/* Data Strobe 0 signal                     	*/
> 
> 
> The header file used to defined the CAEN types (CAENVMEtypes.h) defines 'CAEN_BOOL' like this:
> 
> 
> #ifdef LINUX
> #define CAEN_BYTE   	unsigned char
> #define CAEN_BOOL   	int
> #else
> #define CAEN_BYTE   	byte
> #define CAEN_BOOL   	VARIANT_BOOL
> #endif
> 
> 
> Has anyone ever ran into that problem when setting up an experiment using the CAEN standard?
> 
> Thanks for your help.
> 
> Isaac
    Reply  06 Nov 2020, Isaac Labrie Boulay, Forum, Building an experiment using CAEN VME interface - unknown type name 'VARIANT_BOOL' 



> Hi,
> 
> You're building under Linux like. You want to define the LINUX and skip the VARIANT_BOOL all together.
> PAA
> 
> > Hi everyone,
> > 
> > I have been building an experiment using the v1718 CAEN interface to talk to my modules and I am using the CAENVMElib Linux Library (2.50). I've managed to deal with data type issues by including additional libraries to my driver code but there is one type error 
> that persists:
> > 
> > 
> > In file included from /usr/include/CAENVMElib.h:27:0,
> >              	from include/v1718.h:25,
> >              	from v1718.c:26:
> > /usr/include/CAENVMEtypes.h:323:9: error: unknown type name ‘VARIANT_BOOL’
> >      	CAEN_BOOL cvDS0;  	/* Data Strobe 0 signal                     	*/
> > 
> > 
> > The header file used to defined the CAEN types (CAENVMEtypes.h) defines 'CAEN_BOOL' like this:
> > 
> > 
> > #ifdef LINUX
> > #define CAEN_BYTE   	unsigned char
> > #define CAEN_BOOL   	int
> > #else
> > #define CAEN_BYTE   	byte
> > #define CAEN_BOOL   	VARIANT_BOOL
> > #endif
> > 
> > 
> > Has anyone ever ran into that problem when setting up an experiment using the CAEN standard?
> > 
> > Thanks for your help.
> > 
> > Isaac
    Reply  06 Nov 2020, Isaac Labrie Boulay, Forum, Building an experiment using CAEN VME interface - unknown type name 'VARIANT_BOOL' 
Yes, you are right. That fixed it and my frontend is compiling.

Thanks Pierre-Andre.

Isaac


> Hi,
> 
> You're building under Linux like. You want to define the LINUX and skip the VARIANT_BOOL all together.
> PAA
> 
> > Hi everyone,
> > 
> > I have been building an experiment using the v1718 CAEN interface to talk to my modules and I am using the CAENVMElib Linux Library (2.50). I've managed to deal with data type issues by including additional libraries to my driver code but there is one type error 
> that persists:
> > 
> > 
> > In file included from /usr/include/CAENVMElib.h:27:0,
> >              	from include/v1718.h:25,
> >              	from v1718.c:26:
> > /usr/include/CAENVMEtypes.h:323:9: error: unknown type name ‘VARIANT_BOOL’
> >      	CAEN_BOOL cvDS0;  	/* Data Strobe 0 signal                     	*/
> > 
> > 
> > The header file used to defined the CAEN types (CAENVMEtypes.h) defines 'CAEN_BOOL' like this:
> > 
> > 
> > #ifdef LINUX
> > #define CAEN_BYTE   	unsigned char
> > #define CAEN_BOOL   	int
> > #else
> > #define CAEN_BYTE   	byte
> > #define CAEN_BOOL   	VARIANT_BOOL
> > #endif
> > 
> > 
> > Has anyone ever ran into that problem when setting up an experiment using the CAEN standard?
> > 
> > Thanks for your help.
> > 
> > Isaac
Entry  19 Nov 2020, Joseph McKenna, Forum, History plot consuming too much memory 

A user reported an issue that if they were to plot some history data from 
2019 (a range of one day), the plot would spend ~4 minutes loading then 
crash the browser tab. This seems to effect chrome (under default settings) 
and not firefox

I can reproduce the issue, "Data Being Loaded" shows, then the page and 
canvas loads, then all variables get a correct "last data" timestamp, then 
the 'Updating data ...' status shows... then the tab crashes (chrome)


It seems that the browser is loading all data until the present day (maybe 4 
Gb of data in this case). In chrome the tab then crashes. In firefox, I do 
not suffer the same crash, but I can see the single tab is using ~3.5 Gb of 
RAM

Tested with midas-2020-08-a up until the HEAD of develop

I could propose the user use firefox, or increase the memory limit in 
chrome, however are there plans to limit the data loaded when specifically 
plotting between two dates?
    Reply  19 Nov 2020, Stefan Ritt, Forum, History plot consuming too much memory 
The history code is right now programmes in such a way that when you request
an old time window, then all data from that window until the present date
gets loaded. When we implemented that, this worked fine for data ranges of 
several years with a delay of just a few seconds. Of course one can only
load that specific window, but when the user then scrolls right, one has to
append new data to the "right side" of the array stored in the browser. If the
user jumps to another location, then the browser has to keep track of which 
windows are loaded and which windows not, making the history code much more 
complicated. Therefore I'm only willing to spend a few days of solid work
if this really becomes a problem. 

Are you sure that the delay comes from the browser or actually from mhttpd
digging through GBytes of history data? I realized that you need solid state
disks to get a real quick response.

Stefan
    Reply  20 Nov 2020, Joseph McKenna, Forum, History plot consuming too much memory 
Poking at the behavior of this, its fairly clear the slow response is from the data 
being loaded off an HDD, when we upgrade this system we will allocate enough SSD 
storage for the histories.

Using Firefox has resolved this issue for the user's project here

Taking this down a tangent, I have a mild concern that a user could temporarily 
flood our gigabit network if we do have faster disks to read the history data. Have 
there been any plans or thoughts on limiting the bandwidth users can pull from 
mhttpd? I do not see this as a critical item as I can plan the future network 
infrastructure at the same time as the next system upgrade (putting critical data 
taking traffic on a separate physical network).

> Of course one can only
> load that specific window, but when the user then scrolls right, one has to
> append new data to the "right side" of the array stored in the browser. If the
> user jumps to another location, then the browser has to keep track of which 
> windows are loaded and which windows not, making the history code much more 
> complicated. Therefore I'm only willing to spend a few days of solid work
> if this really becomes a problem. 

For now the user here has retrieved all the data they need, and I can direct others 
towards mhist in the near future. Being able to load just a specific window would be 
very useful in the future, but I comprehend how it would be a spike in complexity.
    Reply  20 Nov 2020, Stefan Ritt, Forum, History plot consuming too much memory 
 > Taking this down a tangent, I have a mild concern that a user could temporarily 
> flood our gigabit network if we do have faster disks to read the history data. Have 
> there been any plans or thoughts on limiting the bandwidth users can pull from 
> mhttpd?

I guess this will not be network limiting but CPU limiting of the mhttpd process. But I'm 
not 100% sure, depends on the actual hardware. But even if we improve the history 
retrieval to "window only", the user could request all data form 2010 to 2020. So one 
would need some code which estimates the amount of data, then tell the user "do you really 
want that?". But still, a novice user can simply click "yes" without much of a thought. So 
in conclusion I believe proper user training is better than software limits. Like the 
other guy "I did 'rm -rf /', and now nothing works any more, can you help?".

Stefan
Entry  24 Nov 2020, Isaac Labrie Boulay, Forum, Invalid name "Analyzer/Tests" 
Hi everyone,

I've recently took the analyzer template from $MIDASSYS/examples/experiment and 
modified it to be able to use Roody on a very simple frontend setup. The 
analyzer works fine and I am able to view the online histograms but my console 
prints out this error:

[Analyzer,ERROR] [odb.cxx:919:db_validate_name,ERROR] Invalid name 
"/Analyzer/Tests/Always true/Rate [Hz]" passed to db_create_key_wlocked: should 
not contain "["                      
[Analyzer,ERROR] [odb.cxx:919:db_validate_name,ERROR] Invalid name 
"/Analyzer/Tests/low_sum/Rate [Hz]" passed to db_create_key_wlocked: should not 
contain "["
[Analyzer,ERROR] [odb.cxx:919:db_validate_name,ERROR] Invalid name 
"/Analyzer/Tests/high_sum/Rate [Hz]" passed to db_create_key_wlocked: should not 
contain "["

The error keeps getting printed even after stopping the run.

I do have these 3 keys under Analyzer/Tests/ in my ODB but I do not know where 
they come from. Any suggestions on what the root of the issue is?

Thanks for the help!

Isaac
    Reply  27 Nov 2020, Konstantin Olchanski, Forum, Invalid name "Analyzer/Tests" 
> I've recently took the analyzer template from $MIDASSYS/examples/experiment and 
> modified it to be able to use Roody on a very simple frontend setup.

Hmm... the old midas analyzer framework is very old and I do not recommend
to use it for new experiments.

A newer analyzer system is ROOTANA and an even newer is the "m" analyzer (manalyzer). These
analyzers progressively introduce improved c++-style programming environments amongst other
improvements. If starting from scratch, I recommend that you use manalyzer (currently from the rootana
git repository).

> The analyzer works fine and I am able to view the online histograms but my console 
> prints out this error:
> 
> [Analyzer,ERROR] [odb.cxx:919:db_validate_name,ERROR] Invalid name 
> "/Analyzer/Tests/Always true/Rate [Hz]" passed to db_create_key_wlocked: should 
> not contain "["

The error says what it means. "[" is not a permitted character in odb names. It is used
by many odb functions to access array elements.

The midas analyzer example should be updated to change "[Hz]" to "(Hz)" or something similar.

K.O.
    Reply  27 Nov 2020, Konstantin Olchanski, Forum, History plot consuming too much memory 
> 
> Tested with midas-2020-08-a up until the HEAD of develop
> 

Just so you know, it took myself and Stefan quite a bit of effort
to improve memory and data handling in the new history plots
to be able to plot 1 year of data without bogging down too much. I got
to learn the google-chrome javascript cpu profiler, memory profiler
and the intricacies of javascript shift() and unshift() operators.

Before midas-2020-08-a, pressing the zoom-out button you would never
reach the javascript memory limit, the code would go into "100% cpu use"
and the browser tab will become progressively unresponsive well before
running out of memory. With the original code, our alpha-g history plots
could go back a few weeks at most, with the current code, we can go back
about 11 months. Compared to the old "C" history plots that can
do "last 10 years", no problem.

Loading all the history data into the browser is a design choice.

It has benefits and downsides.

The main benefit is that looking at immediate live data is much easier.

The main downside is that "plot last 10 years" becomes impossible.

As they say "appetite comes during eating", we have learned about these
downsides as we developed the new system. When we started, we did not
know much about javascript memory limits, cpu limits, etc. We did learn
a lot, though.

With the current code, we are limited to loading history data up to 50% of
the javascript memory limit. I know how to change the code to get up to 100%,
but I think it is not worth it, it still does not get as to plot "last 10 year".

We think the solution to recovering "last 10 years" capability is to use
binned data (which the history system can already deliver to javascript).
With binned data, the data volume in Mbytes remains constant, javascript
memory use has an upper-bound (we never use more memory than X Mbytes)
and data movement over the network is reduced.

Another way to look at this - typical display has only 1000-4000 vertical pixels,
it cannot physically display a bigger number of data points (no more
then 1 data point per pixel). So why load 1000000 data points when we only
can plot 1000-4000 of them?

So all the infrastructure for plotting binned data is already there,
but the javascript code still needs to be written. I think the biggest
challenge will be in blending or combining binned and unbinned data
on the same plot or in seamlessly switching the plot between binned and
unbinned data.

K.O.
    Reply  27 Nov 2020, Konstantin Olchanski, Forum, History plot consuming too much memory 
>
> With the current code, we are limited to loading history data up to 50% of
> the javascript memory limit.
>

The javascript memory limit itself seems to be a moving target. (google javascript 
memory limit, and good luck!).

Historically, javascript did not have any memory or cpu use limits, but with
the raise of abusive web sites, bitcoin miners, etc, I see browsers clamp down
on allowed/allocated CPU use (inactive tabs are throttled down). memory use
is already clamped down severely, on a 64 GB computer, a browser tab
can only allocate a handful of GBs.

This throttling of browser tabs is already intrusive enough that we need
to be careful in programming midas web pages. for examples throttled events
are not firing at the same rate or in the same order as in active tabs.

One logical conclusion of these restrictions could be that, eventually,
google-chrome permits only just enough cpu and memory to run gmail.

K.O.
    Reply  27 Nov 2020, Konstantin Olchanski, Forum, History plot consuming too much memory 
> 
> Are you sure that the delay comes from the browser or actually from mhttpd
> digging through GBytes of history data?
>

I think we will need to address this question "head-on". The history plot
will need to display the following information:

"time to load data from disk: N seconds, time to transfer data to javascript: M 
seconds, time to make the plot: Q seconds".

The second and third items are already available, the first one will need
to be computed in mhttpd and passed to javascript.

K.O.
    Reply  27 Nov 2020, Konstantin Olchanski, Forum, History plot consuming too much memory 
>
> Taking this down a tangent, I have a mild concern that a user could temporarily 
> flood our gigabit network if we do have faster disks to read the history data.
>

By my measurements, right now our javascript code can reach 30-50-70% of Gige ethernet
bandwidth, so, no, we cannot flood the network just by making history plots.

(we cannot reach 100% because javascript code is not multithreaded,
it cycles through "request new data" and "decode javascript, make plot" states,
and the network is idle in this second state).

>
> Have there been any plans or thoughts on limiting the bandwidth users can pull from 
> mhttpd?
>

10gige networking is here (and 5 and 2.5 Gige, too). I would not worry too much
about saturating 1gige network interfaces.

>
> I do not see this as a critical item as I can plan the future network 
> infrastructure at the same time as the next system upgrade (putting critical data 
> taking traffic on a separate physical network).
>

10gige network between all computers, everything on SSD ZFS arrays, except
bulk data on ZFS HDD arrays (only for cost reasons $$$/TB).

K.O.
    Reply  27 Nov 2020, Konstantin Olchanski, Forum, Building an experiment using CAEN VME interface - unknown type name 'VARIANT_BOOL' 
> 
> The header file used to defined the CAEN types (CAENVMEtypes.h) defines 'CAEN_BOOL' like this:
> 
> 
> #ifdef LINUX
> #define CAEN_BYTE   	unsigned char
> #define CAEN_BOOL   	int
> #else
> #define CAEN_BYTE   	byte
> #define CAEN_BOOL   	VARIANT_BOOL
> #endif
> 

Complain to CAEN.

The year is 2020 and they should use standard C/C++ data types from stdint.h (uint32_t, etc).

K.O.
    Reply  27 Nov 2020, Konstantin Olchanski, Forum, Invalid name "Analyzer/Tests" 
https://bitbucket.org/tmidas/midas/issues/298/invalid-odb-names-in-example-midas
K.O.
    Reply  01 Dec 2020, Stefan Ritt, Forum, subrun  
There is no "mechanism" foreseen to be executed after each subrun. But you could 
run a shell script after each run which loops over all subruns and converts them 
one after the other.

Stefan

> Hi,
> 
> I was wondering if there is a "mechanism" to run an executable
> file after each subrun is closed...
> 
> I need to convert .mid.lz4 subrun files to ROOT (TTree) files;
> 
> Thanks,
> Gennaro
    Reply  01 Dec 2020, Ben Smith, Forum, subrun  
We use the lazylogger for something similar to this. You can specify the path to a custom script, and it will be run for each midas file that gets written:
https://midas.triumf.ca/MidasWiki/index.php/Lazylogger#Using_a_script
This means that you don't have to wait until the end of the run to start processing.

If the ROOT conversion is going to be slow, but you have a batch system available, you could use the lazylogger script to submit a job to the batch system for each file.

> 
> > Hi,
> > 
> > I was wondering if there is a "mechanism" to run an executable
> > file after each subrun is closed...
> > 
> > I need to convert .mid.lz4 subrun files to ROOT (TTree) files;
> > 
> > Thanks,
> > Gennaro
    Reply  07 Dec 2020, Isaac Labrie Boulay, Forum, Invalid name "Analyzer/Tests" 
> https://bitbucket.org/tmidas/midas/issues/298/invalid-odb-names-in-example-midas
> K.O.

Hi K.O.

Ok I see, I will use the most up to date analyzer.

Thanks a ton for your help.

Isaac
Entry  09 Dec 2020, Frederik Wauters, Forum, history and variables confusion 
I have a fe, with 2 "equipments" (2 different types of LV supplies).

Equipment/../Setting has a "Names" key, with the actual channel names (ch1, ch2, ...) of the devices.

Equipment/../Variables has channel states, voltage, etc. 

I also write a separate midas bank for each supply.

When I turn the "Log History" on, 2 things happen which cause troubles:
1. It writes the data of both bank to both the /Equipment/(Device1/Device2)/Variables .
2. I have e.g. 4 channels. In the banks I write current and voltages, so 8 numbers. When I turn on the logger I get an "Array size mismatch" between names and the midas bank size.

The only way around this is to disable the history logging in the equipment, and set "virtual" History events?
    Reply  09 Dec 2020, Stefan Ritt, Forum, history and variables confusion 
First, the writing of banks is completely independent of the history system. Banks go to the log file only, 
while the history is only linked to the "Variables" section in the ODB.

Second, it's advisable to group similar equipment into one. Like if you have five power supplies powering
and experiment, you don't want to have five equipments Supply1, Supply2, ..., but only one equipment
"Power Supplies". In the frontend belonging to that equipment, you define a DEVICE_DRIVER list with
one entry for each power supply. If you interact with an mscb device, there are some helper functions
which simplify the definition of the equipment and which I can send you privately. So your device
driver looks a bit like the one attached.

If you cannot do that and absolutely want separate equipments, please post a complete ODB subtree of your
settings, and I can try to reproduce your problem.

Stefan

======================

DEVICE_DRIVER power_driver[] = {
   {"Power Supply 1", mscbdev, 0, NULL, DF_INPUT | DF_MULTITHREAD},
   {"Power Supply 2", mscbdev, 0, NULL, DF_INPUT | DF_MULTITHREAD},
   {"Power Supply 3", mscbdev, 0, NULL, DF_INPUT | DF_MULTITHREAD},
   {""}
};

...

INT frontend_init()
{
   mscb_define("mscbxxx.psi.ch", "Power Supplies", "Power Supply 1", power_driver, 1, 0, "Output 1", 0.1);
   mscb_define("mscbxxx.psi.ch", "Power Supplies", "Power Supply 1", power_driver, 1, 1, "Output 2", 0.1);
   ...
}

/*-- Function to define MSCB variables in a convenient way ---------*/

void mscb_define(const char *submaster, const char *equipment, const char *devname, 
                 DEVICE_DRIVER *driver, int address, unsigned char var_index, 
                 const char *name, double threshold)
{
   int i, dev_index, chn_index, chn_total;
   char str[256];
   float f_threshold;
   HNDLE hDB;

   cm_get_experiment_database(&hDB, NULL);

   if (submaster && submaster[0]) {
      sprintf(str, "/Equipment/%s/Settings/Devices/%s/Device", equipment, devname);
      db_set_value(hDB, 0, str, submaster, 32, 1, TID_STRING);
      sprintf(str, "/Equipment/%s/Settings/Devices/%s/Pwd", equipment, devname);
      db_set_value(hDB, 0, str, "meg", 32, 1, TID_STRING);
   }

   /* find device in device driver */
   for (dev_index=0 ; driver[dev_index].name[0] ; dev_index++)
      if (equal_ustring(driver[dev_index].name, devname))
         break;

   if (!driver[dev_index].name[0]) {
      cm_msg(MERROR, "mscb_define", "Device \"%s\" not present in device driver list", devname);
      return;
   }

   /* count total number of channels */
   for (i=chn_total=0 ; i<=dev_index ; i++)
      if (((driver[dev_index].flags & DF_INPUT) > 0 && (driver[i].flags & DF_INPUT)) ||
          ((driver[dev_index].flags & DF_OUTPUT) > 0 && (driver[i].flags & DF_OUTPUT)))
      chn_total += driver[i].channels;

   chn_index = driver[dev_index].channels;
   sprintf(str, "/Equipment/%s/Settings/Devices/%s/MSCB Address", equipment, devname);
   db_set_value_index(hDB, 0, str, &address, sizeof(int), chn_index, TID_INT, TRUE);
   sprintf(str, "/Equipment/%s/Settings/Devices/%s/MSCB Index", equipment, devname);
   db_set_value_index(hDB, 0, str, &var_index, sizeof(char), chn_index, TID_BYTE, TRUE);

   if (threshold != -1 && (driver[dev_index].flags & DF_INPUT) > 0) {
     sprintf(str, "/Equipment/%s/Settings/Update Threshold", equipment);
     f_threshold = (float) threshold;
     db_set_value_index(hDB, 0, str, &f_threshold, sizeof(float), chn_total, TID_FLOAT, TRUE);
   }

   if (name && name[0]) {
      sprintf(str, "/Equipment/%s/Settings/Names %s", equipment, devname);
      db_set_value_index(hDB, 0, str, name, 32, chn_total, TID_STRING, TRUE);
   }

   /* increment number of channels for this driver */
   driver[dev_index].channels++;
}
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