> Hi, Stefan - is this our famous 64-bit misalignement? Where we have each alternating bank aligned and misaligned at 64 bits? Without changing the data
> format, one can always store data in 64-bit aligned banks by inserting a dummy banks between real banks:
> 
> event header
> bank header
> bank1 --- 64-bit aligned --- with data
> bank2 --- misaligned, no data
> bank3 --- 64-bit aligned --- with data
> bank4 --- misaligned, no data
> ...
> 
> for sure, wastes space for bank2, bank4, etc, but at 12 bytes per bank, maybe this is negligible overhead compared to total event size.
> 
> BTW, aligned-to-64-bit is old news. The the PWB FPGA, I have 128-bit data paths to DDR RAM, the data has to be aligned to 128 bits, or else!

Ok, so what about the following: When we do a bk_init32, we add a parameter "alignment", which might be 1,4,8,16 and "old". We store this alignment in the bank header, so the 
decoding works correctly. Now "old" means the current encoding, which is screwed up and produces the results you mention above, but we have to keep it (actually make it the 
default!) for backward compatibility. But then we can ask for 64-bit alignment or even 128-bit alignment if that helps the DAQ speed.

The only problem I see is if one writes data with the new library using 128-bit alignment for example, and wants to read it back with old code. Then it would explode. So if we 
make this modification, we have to announce it carefully and also adjust all ROOTANA & Co libraries to read back any midas data.

Stefan

> > We also agree and found the problem now.
> 
> Good. what was wrong?
> 
> > - Own DMA engine since we are doing burst writing DMA with PCIe 3.0. 
> > - Own device driver
> 
> Scary stuff.
> 
> > - no interrupts 
> 
> Right. Best I can tell, interrupts no longer useful in Linux - interrupt handler cannot do any real work, has to hand off to a kernel thread, resulting
> in so much latency and overhead that one might as well poll for the data... And for DMA data transfers, the data rate is well known,
> so easy to predict how long the DMA will run for and sleep for that amount of time instead of waiting for an interrupt.
> 
> K.O.

So the problem was that we assumed that the bank (with the header) needs to be 64bit aligned. Even more we aligned the hole Midas event to 256bit in the fpga since we have a  250mhz x 256 Bit interface for PCIe. But then we saw that you align the bank data to 64bit -> crash of mdump etc. For now we generate the data on the FPGA in the „old“ Midas format. So having a flag for changing to a different alignment would be actually really nice. 

Cheers,
Marius

Dear all,

in 13 Feb 2020 to 21 Feb 2020 we had a talk about how I try to create MIDAS events directly on a FPGA and 
than use DMA to hand the event over to MIDAS. In the thread I also explained how I do it in my MIDAS frontend. 

For testing the DAQ I created a dummy frontend which was emulating my FPGA (see attached file). The interesting code is 
in the function read_stream_thread and there I just fill a array according to the 32b BANKS which are 64b aligned (more or less
the lines 306-369). And than I do:

    uint32_t * dma_buf_volatile;
    dma_buf_volatile = dma_buf_dummy;

    copy_n(&dma_buf_volatile[0], sizeof(dma_buf_dummy)/4, pdata);

    pdata+=sizeof(dma_buf_dummy);
    rb_increment_wp(rbh, sizeof(dma_buf_dummy)); // in byte length

to send the data to the buffer.

This summer (Mai - July) everything was working fine but today I did not get the data into MIDAS. 
I was hopping around a bit with the commits and everything was at least working until: 3921016ce6d3444e6c647cbc7840e73816564c78.

Thanks,
Marius

> today I did not get the data into MIDAS. 

Any error messages printed by the frontend? any error message in midas.log? core dumps? crashes?

I do not understand what you mean by "did not get the data into midas". You create events
and send them to a midas event buffer and you do not see them there? With mdump?
Do you see this both connected locally and connected remotely through the mserver?

BTW, I see you are using the mfe.c frontend. Event data handling in mfe.c frontends
is quite convoluted and impossible to straighten out. I recommend that you use
the tmfe c++ frontend instead. Event data handling is much simplified and is easier to debug
compared to the mfe.c frontend. There is examples in the midas repository and there are
tutorials for converting frontends from mfe.c to tmfe posted in this forum here.

BTW, the commit you refer to only changed some html files, could not have affected
your data.

K.O.

> Any error messages printed by the frontend? any error message in midas.log? core dumps? crashes? 
> I do not understand what you mean by "did not get the data into midas". You create events
> and send them to a midas event buffer and you do not see them there? With mdump?
> Do you see this both connected locally and connected remotely through the mserver?

I simply don't see the event counter counting up and I also don't see them using mdump. No logs, no dumps and no crashes - every is quite. I only tested it locally.
 
> BTW, I see you are using the mfe.c frontend. Event data handling in mfe.c frontends
> is quite convoluted and impossible to straighten out. I recommend that you use
> the tmfe c++ frontend instead. Event data handling is much simplified and is easier to debug
> compared to the mfe.c frontend. There is examples in the midas repository and there are
> tutorials for converting frontends from mfe.c to tmfe posted in this forum here.

I know the code I used is really old that's why I was so surprised that it suddenly did not work. But I am on the way to change it. Also Stefan gave me some comments on how to improve the code. But still changing them did not really change the behavior. 

> BTW, the commit you refer to only changed some html files, could not have affected
> your data.

I just hopped around and the commit I send was the first one which worked again. But it's of course not the one where the stuff broke. I did a bit of git-bisect and ended up with this commit as the first one where my frontend is not working anymore: 91582e4172d534bf9b10e661a423c399fd1a69f4

Cheers,
Marius

> 
> > Any error messages printed by the frontend? any error message in midas.log? core dumps? crashes? 
> > I do not understand what you mean by "did not get the data into midas". You create events
> > and send them to a midas event buffer and you do not see them there? With mdump?
> > Do you see this both connected locally and connected remotely through the mserver?
> 
> I simply don't see the event counter counting up and I also don't see them using mdump. No logs, no dumps and no crashes - every is quite. I only tested it locally.
>

If you are connected locally (no mserver), I want to know the value returned by bm_send_event(). Simplest
if you edit mfe.c and everywhere it calls bm_send_event() and rpc_send_event(), print the returned value.

It would be very interesting to see if bm_send_event() returns 1 (SUCCESS), but the event vanishes
without a trace.

Before you do that, try something simpler:

Run "mdump -s -d", it will print some event buffer internals.

Watch to see if any data pointers change when you send your events ("wp", "rp", etc).

If nothing changes at all, then we are not sending anything (fault is in your code or on mfe.c).

If you see "wp" counting up, then we definitely write your events into the buffer and mdump & mlogger should see them.

But there is some funny logic for event_id and trigger_mask and it is worth checking their
values. For a good test, set event_id=1 and trigger_mask=0x1. There might be trouble if either is set to zero.

K.O.

> If you are connected locally (no mserver), I want to know the value returned by bm_send_event(). Simplest
> if you edit mfe.c and everywhere it calls bm_send_event() and rpc_send_event(), print the returned value.
> 
> It would be very interesting to see if bm_send_event() returns 1 (SUCCESS), but the event vanishes
> without a trace.

I checked bm_send_event(rbh, (EVENT_HEADER*)(&pdata[0]), 0, 20); which gives me back 1. I also check the status of rb_increment_wp which is also 1.

> Before you do that, try something simpler:
> Run "mdump -s -d", it will print some event buffer internals.
> Watch to see if any data pointers change when you send your events ("wp", "rp", etc).

"rp" & "wp" are not counting up. 

> But there is some funny logic for event_id and trigger_mask and it is worth checking their
> values. For a good test, set event_id=1 and trigger_mask=0x1. There might be trouble if either is set to zero.

Changing both to 0x1 did not change the behavior. 

Cheers,
Marius

I finally got the dummy program working. There were several issues:

- event_buffer_size was defined as 10000 * 32 MB = 320 GB, exceeding the RAM of the computer

- SERIAL number starting with 1. Actually in midas, event serial numbers always started with zero, but this was wrong in the documentation at 
https://midas.triumf.ca/MidasWiki/index.php/Event_Structure, so I also fixed the documentation

- the event header time stamp must be seconds since 1.1.1970, and thus the function ss_time() should be used to set it

- calling set_equipment_status() for each event slows down the event collection considerably, since this function access the ODB each time

- dma_buf_dummy is defined inside the event loop, so it gets allocated and de-allocated on the stack for each event. Of course this might vanish 
when the real FPGA buffer will be used.

- The line pdata+=sizeof(dma_buf_dummy); is wrong. pdata is pointer to uint32_t, but the sizeof() operation returns the size of the 
dma_buf_dummy in bytes. Therefore, pdata gets incremented by four times the size of dma_buf_dummy

- Instead the call to std::this_thread::sleep_for(std::chrono::milliseconds(2000)); one can call the standard midas call ss_sleep(2000); which 
is a bit shorter

- Finally, sending many events to the ring buffer triggered a bug in the midas ring buffer functions which were lingering there since 2007. I'm 
glad that this happened and now could be fixed. Not sure if other experiments where affected in the last decade by that. This could have 
manifested itself in lost events or crashing front-ends. Anyhow, now it's fixed. You need to update midas to get the fix.

I attached a working version of the dummy program for your reference. Banks a different but the principle should become clear.

Stefan

I just came back to this and started to use the dummy frontend.
Unfortunately, I have a problem during run cycles: 

Starting the frontend and starting a run works fine -> seeing events with mdump and also on the web GUI. 
But when I stop the run and try to start the next run the frontend is sending no events anymore.
It get stuck at line 221 (if (status == DB_TIMEOUT)).
I tried to reduce the nEvents to 1 which helped in terms of DB_TIMEOUT but still I don't get any events after I did a stop / start cycle -> no events in mdump and no events counting up at the web GUI.
If I kill the frontend in the terminal (ctrl+c) and restart it, while the run is still running, it starts to send events again.

Cheers,
Marius

> Starting the frontend and starting a run works fine -> seeing events with mdump and also on the web GUI. 
> But when I stop the run and try to start the next run the frontend is sending no events anymore.
> It get stuck at line 221 (if (status == DB_TIMEOUT)).
> I tried to reduce the nEvents to 1 which helped in terms of DB_TIMEOUT but still I don't get any events after I did a stop / start cycle -> no events in mdump and no events counting up at the web GUI.
> If I kill the frontend in the terminal (ctrl+c) and restart it, while the run is still running, it starts to send events again.

This problem has (likely) been fixed in the current version. Please pull develop and try again. Was a recursive call to the event collection routine which is only triggered if you send events faster than 
the logger can digest, so not many people see it.

Best,
Stefan

> This problem has (likely) been fixed in the current version. Please pull develop and try again. Was a recursive call to the event collection routine which is only triggered if you send events faster than 
> the logger can digest, so not many people see it.

I just pulled the current version (d945fa9) but the problem as explained in 2347 stays the same.

Best,
Marius

I finally found the problem why the readout stops after a run transition. 

In my dummy frontend the serial number was not reset to zero at run start. 
This leads to a mismatch of the serial number in the function receive_trigger_event of mfe.cxx:1247.
Which is than resulting in the problem that the function founds never a new event in all ring buffers and nothing get read out of the buffer.

Nevertheless, it would be nice that the system would tell the user that there is a mismatch in the serial number (printing a warning / error etc.). 

Cheers,
Marius

Hi,

I am having some trouble with the data in my Midas bank. I am filling a midas
bank in my frontend (one of several in my system), and this bank is then being
added to the overall event by the event builder.

I check the data as it enters the bank, and also check again after I close the
bank in my frontend (using pdata's original value), and in both cases my data is
as I expect.

However, when I view the data in the .mid file (using mdump), there is a
problem. The correct number of words are there, and the values are correct up
until the 148th word. However, all subsequent words are 0.

I have also noticed that if I change my word size from 32bit (DWORD) to 16bit
(WORD), I observe the same behaviour except that now the first 296 words are
correct and all others are zero.

Note that other frontends in the system are not suffering this issue.

Does anyone have any ideas about how to solve this problem?

In the old SVN midas world it was typically such that the Windows dll's and
exe's were ready to be used when checking out. I am not so sure this is the case
for the current version, since when I use the packed dll's  and exe's (e.g.
odbedit.exe) I get the warning that this is running midas 2.0.0 but the current
version (on the linux server) is 2.1.

What does this mean?

1) A little bug in the packed windows part, but up-to-date dll's and exe's?
2) The dll's and exe's are not bundled any more to up-to-date version?

If 2) is the case, I would like to get a hint how to build midas under Windows
(Windows 7), since we still have some few Windows clients.  

> In the old SVN midas world it was typically such that the Windows dll's and
> exe's were ready to be used when checking out.

The Windows executables are no longer included in the midas git repository. Old versions are still available in 
the git repository - they got pulled in during conversion from svn.

One reason for removing them is that neither myself, nor Pierre, nor Stefan have ready access to a Windows 
development environment and we cannot keep Windows binaries up to date. Theoretically we can setup a 
Windows machine just for compiling MIDAS, but then there is a question of which Windows we should use and 
how much priority we should put into it. I do not think there is any demand for MIDAS on Windows at TRIUMF.

(Personally, I think Windows is no longer a viable platform for any business use - with Microsoft focusing on 
"experiences", "tiles", touch screens, portable devices, and other gimmicks - rather than on providing a solid OS 
to get work done)

> I am not so sure this is the case
> for the current version, since when I use the packed dll's  and exe's (e.g.
> odbedit.exe) I get the warning that this is running midas 2.0.0 but the current
> version (on the linux server) is 2.1. What does this mean?

You can ignore this message. Stefan incremented the MIDAS version when we migrated to git, but
there are no changes to the MIDAS RPC mechanism and we are still fully compatible with old versions,
at least in the MIDAS RPC and in the mserver.

So tools like odbedit.exe should still work okey when connecting from Windows to MIDAS running on Linux or 
MacOS.

But old frontend programs may cause some trouble because the ODB layout changed somewhat with new things 
added to /eq/xxx/common. Simplest is to try, if it works, it works.

> 1) A little bug in the packed windows part, but up-to-date dll's and exe's?
> 2) The dll's and exe's are not bundled any more to up-to-date version?

Case (2) is the case. Personally I do not have any capability to build Windows binaries. Same for Pierre and I think 
for Stefan.

> If 2) is the case, I would like to get a hint how to build midas under Windows
> (Windows 7), since we still have some few Windows clients.  

I do not think pre-built executables will ever return - the new way of things is to "cut-and-paste" the "git clone" 
command from a web page, type "make", and be done with it. If your OS does not have "git", "make" & etc, you 
should switch to a real OS.

On the MIDAS software side, we have no problem with supporting Windows - same as on any other platform, 
please try to build and run it, report any problems, fixes, patches and improvements - we will commit them into 
the midas repository.

K.O.

> The Windows executables are no longer included in the midas git repository. Old versions are still available in 
> the git repository - they got pulled in during conversion from svn.
> 
> One reason for removing them is that neither myself, nor Pierre, nor Stefan have ready access to a Windows 
> development environment and we cannot keep Windows binaries up to date. Theoretically we can setup a 
> Windows machine just for compiling MIDAS, but then there is a question of which Windows we should use and 
> how much priority we should put into it. I do not think there is any demand for MIDAS on Windows at TRIUMF.

I double checked and can confirm that the executables in GIT are very old. So I tried to compile the current version for Windows. I found that I had to change lots 
of places (basically all the new files written by KO) to make it work again, so it took me half a day, but now should be fine.

I'm not sure if it's a good idea to keep .exe files in GIT, maybe we should remove it some day, but for the moment I updated the executables to the current 
version. Feedback welcome.

/Stefan

Hello, 
I'm trying to make Wiener PCIVME link work with MIDAS. 
In documentation/VME dirvers/ it's saying: "wevmemm.c PCI/VME Wiener board
supported. (see Wiener PCI)".
Provided link is dead. Does anyone have that file? I would appreciate very very
much if someone could send it to me.

Thank you and best regards, 
L.P.

> Hello, 
> I'm trying to make Wiener PCIVME link work with MIDAS. 
> In documentation/VME dirvers/ it's saying: "wevmemm.c PCI/VME Wiener board
> supported. (see Wiener PCI)".
> Provided link is dead. Does anyone have that file? I would appreciate very very
> much if someone could send it to me.
> 
> Thank you and best regards, 
> L.P.

Hi, I am not familiar with this module, I am pretty sure I have never seen one.
I do not see any code for it in the midas distribution.
I do not see any reference to it on the wiener web site (http://www.wiener-d.com/)

For obsolete modules, they direct us to http://file.wiener-d.com/ which is dead.

The next best step is to contact Wiener customer support. They usually reply very quickly.

If you have no luck getting answer directly from Wiener, you can ask me to contact them through
our sales representative. He is always super very helpful.

K.O.

> > Hello, 
> > I'm trying to make Wiener PCIVME link work with MIDAS. 
> > In documentation/VME dirvers/ it's saying: "wevmemm.c PCI/VME Wiener board
> > supported. (see Wiener PCI)".
> > Provided link is dead. Does anyone have that file? I would appreciate very very
> > much if someone could send it to me.
> > 
> > Thank you and best regards, 
> > L.P.
> 
> Hi, I am not familiar with this module, I am pretty sure I have never seen one.
> I do not see any code for it in the midas distribution.
> I do not see any reference to it on the wiener web site (http://www.wiener-d.com/)
> 
> For obsolete modules, they direct us to http://file.wiener-d.com/ which is dead.
> 
> The next best step is to contact Wiener customer support. They usually reply very quickly.
> 
> If you have no luck getting answer directly from Wiener, you can ask me to contact them through
> our sales representative. He is always super very helpful.
> 
> K.O.

Hi, 
I'm having a meeting with Wiener during this weekend, I'll try to dig some info about that module. But I do recall that we had this interface and provided a driver for it.
More later... 
PAA

> > Hello, 
> > I'm trying to make Wiener PCIVME link work with MIDAS. 
> > In documentation/VME dirvers/ it's saying: "wevmemm.c PCI/VME Wiener 
board
> > supported. (see Wiener PCI)".
> > Provided link is dead. Does anyone have that file? I would appreciate 
very very
> > much if someone could send it to me.
> > 
> > Thank you and best regards, 
> > L.P.
> 
> Hi, I am not familiar with this module, I am pretty sure I have never 
seen one.
> I do not see any code for it in the midas distribution.
> I do not see any reference to it on the wiener web site 
(http://www.wiener-d.com/)
> 
> For obsolete modules, they direct us to http://file.wiener-d.com/ which 
is dead.
> 
> The next best step is to contact Wiener customer support. They usually 
reply very quickly.
> 
> If you have no luck getting answer directly from Wiener, you can ask me 
to contact them through
> our sales representative. He is always super very helpful.
> 
> K.O.

Hi, I do recall that we had this interface a while ago. 
I'll be meeting with Wiener during the weekend and will post my findings 
later. 
PAA