Argonne National Laboratory

Experimental Physics and
Industrial Control System

1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  <2017 Index 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  <2017
<== Date ==> <== Thread ==>

Subject: RE: Area Detector and high performance NVME devices
From: Mark Rivers <rivers@cars.uchicago.edu>
To: "Mark S. Engbretson" <Engbretson@anl.gov>, "tech-talk@aps.anl.gov" <tech-talk@aps.anl.gov>
Date: Tue, 27 Jun 2017 19:47:47 +0000
Hi Mark,

I just tried with simDetector on a Windows 7 system with 8 cores, 15K RPM SAS Raid-0 disk, 96 GB RAM.

4096 x 3078 Int8 images = 12 MB/image.

The simDetector is generating about 150 frames/s = 1.8 GB/s.

This is the output of camonitor on the ArrayRate_RBV and WriteFile_RBV PVs in the HDF5 plugin:

corvette:simDetectorIOC/iocBoot/iocSimDetector>camonitor -tc 13SIM1:HDF1:ArrayRate_RBV 13SIM1:HDF1:WriteFile_RBV
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:21.809029) 0
13SIM1:HDF1:WriteFile_RBV      (2017-06-27 14:15:21.809162) Done
13SIM1:HDF1:WriteFile_RBV      (2017-06-27 14:15:31.451841) Writing STATE MINOR
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:33.410624) 34
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:34.411782) 54
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:35.410801) 55
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:37.408966) 52
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:38.408085) 54
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:39.407156) 48
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:40.408254) 53
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:41.409449) 55
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:42.410515) 45
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:43.411498) 50
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:44.411601) 47
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:45.410666) 53
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:46.409790) 50
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:47.408919) 54
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:48.407977) 53
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:49.407138) 52
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:50.408088) 60
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:51.409265) 62
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:52.410457) 52
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:53.411547) 59
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:54.411524) 62
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:55.411724) 55
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:56.410814) 60
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:57.409946) 57
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:58.408960) 59
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:15:59.407069) 60
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:00.408095) 42
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:01.409358) 17
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:02.410576) 27
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:03.411677) 25
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:04.413487) 27
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:05.411605) 25
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:06.411612) 24
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:07.409803) 23
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:11.410220) 19
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:12.411320) 18
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:13.412261) 21
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:15.412525) 20
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:16.411553) 22
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:17.410808) 24
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:20.409031) 28
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:21.411129) 25
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:22.411199) 24
13SIM1:HDF1:WriteFile_RBV      (2017-06-27 14:16:22.818068) Done
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:23.412388) 1
13SIM1:HDF1:ArrayRate_RBV      (2017-06-27 14:16:24.413361) 0

So for the first 25 seconds or so it is writing at about 55 frames/s = 660 MB/s.  This is probably filling the Windows file cache.  It then slows down to about 23 frames/s = 280 MB/s, which is probably the steady state write speed of the disks.

So I agree that it will probably be difficult to write HDF5 files at the full rate of your camera, which is 190 frame/s = 2.3 GB/s.

One possible solution would be to write your RAW files that can keep up, and also write HDF5 files of "thumbnail" data that is either cropped or binned to 512x384 for example.  You can then store all the metadata in the HDF file and the images in the RAW file.  Later on you can either merge these 2 files into a large HDF5 file, or just keep them separate.

Mark

________________________________
From: Mark S. Engbretson [Engbretson@anl.gov]
Sent: Tuesday, June 27, 2017 1:51 PM
To: Mark Rivers; tech-talk@aps.anl.gov
Subject: RE: Area Detector and high performance NVME devices

I do not have enough memory to create a queue large enough to buffer all the images.  2BM wants to acquire the camera stream for at least 15 minutes and ideally as long as possible. So talking about 2-4 TB.  Or larger if the buy  huge nvme chips or multiple turbo Z units – the computer supports having 3 of them.

I have allocated very large buffers, but for a 4096 by 3078 image being created at 190 FPS, the file plugins would have to be able to keep up . . . and they don’t.

Using the SimDetector, I can create such images at ~260 FPS. HDF is only writing the file out at about 60 FPS, using whatever the defaults settings. NetCFD writes about 30 FPS.  A buffer of 4000 in both cases only lasted for about a minute. The raw file plugin slows the simDetector acquire rate to about 170-180 FPS, which the plugin can keep up with. The stardardarray plugin by itself also slows simDetecor to about  the same thing.


From: Mark Rivers [mailto:rivers@cars.uchicago.edu]
Sent: Tuesday, June 27, 2017 1:06 PM
To: 'Mark S. Engbretson' <Engbretson@anl.gov>; tech-talk@aps.anl.gov
Subject: RE: Area Detector and high performance NVME devices

Hi Mark,

I am surprised that a raw file plugin is significantly faster than netCDF or HDF5.  I would like to see the tests, and figure out what is actually slowing them down, i.e. is it CPU bound, waiting for a semaphore, etc.?  Can you post actual benchmark results for the different plugins, i.e. frames/s and MB/s?

You should not need to do anything special to create a FIFO to buffer images while the disk is busy.  Every areaDetector plugin comes with such a FIFO, i.e. its input queue.  Just increase the QueueSize to be large enough to buffer all the images you need to store in one "burst".  You can also use the CircularBuffer plugin to do this, but it should really not be necessary, that is intended more for "triggered" applications where the buffer is emptied when a trigger condition is satisfied.

Mark


From: Mark S. Engbretson [mailto:Engbretson@anl.gov]
Sent: Tuesday, June 27, 2017 12:24 PM
To: Mark Rivers; tech-talk@aps.anl.gov<mailto:tech-talk@aps.anl.gov>
Subject: Area Detector and high performance NVME devices

Mark –

I have the adimec camera which generates data at  ~2.5 GB/s. I recently got my hands on a newer HP 840 with a HP Turbo Z nvme drive which claims a sustained write speed of 6 GB/S. None of the existing file plugin see any performance increase when writing to this device – I do not think that any are actually write limited.  I have modified a raw binary file plugin that I obtained from Keenan Lang that easily sustains the cameras write rate until the device is full.

Problem is – Raw data really doesn’t do anyone much good. I was thinking that perhaps a quick solution to my problem might be to change this Raw File plugin to look/act like a disk based fifo or circular buffer. This could collect to the limit of the hardware at full speed, and if someone wanted HDF output, they would just drain this queue at the speed that HDF files are generated.  Or is there an easier/better solution? I.e. any way that file plugins can use the new multi-thread model of AD 3.0?

I know the HDF files can be generates at very high speeds on Lustre file systems, but this seems to be using parallel HDF5. Is this something that Area Detector supports?

Replies:
RE: Area Detector and high performance NVME devices Mark S. Engbretson
References:
Area Detector and high performance NVME devices Mark S. Engbretson
RE: Area Detector and high performance NVME devices Mark Rivers
RE: Area Detector and high performance NVME devices Mark S. Engbretson

Navigate by Date:
Prev: RE: Area Detector and high performance NVME devices Mark S. Engbretson
Next: RE: Area Detector and high performance NVME devices Mark S. Engbretson
Index: 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  <2017
Navigate by Thread:
Prev: RE: Area Detector and high performance NVME devices Mark S. Engbretson
Next: RE: Area Detector and high performance NVME devices Mark S. Engbretson
Index: 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  <2017
ANJ, 27 Jun 2017 Valid HTML 4.01! · Home · News · About · Base · Modules · Extensions · Distributions · Download ·
· EPICS V4 · IRMIS · Talk · Bugs · Documents · Links · Licensing ·