 22 Dec 2005, Konstantin Olchanski, Info, How do I do custom event building?
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It turns out the the standard event builder fragment matching algorithm cannot
be used in my TPC application. I have two TPC-USB interfaces, which lack any
"busy" or synchronization logic. I send the hardware trigger into both
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 23 Dec 2005, Stefan Ritt, Info, midas max event size?
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> My TPC events are fairly large: 18 FEC cards * 128 channels per card * 2 Kbytes
> per channel = about 4 Mbytes. In my
> frontend, when I request this event size, MIDAS complaints (in mfe.c) that it is
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23 Dec 2005, Stefan Ritt, Info, How do I do custom event building?
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> It turns out the the standard event builder fragment matching algorithm cannot
> be used in my TPC application. I have two TPC-USB interfaces, which lack any
> "busy" or synchronization logic. I send the hardware trigger into both
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03 Jan 2006, John O'Donnell, Info, How do I do custom event building?
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At DANCE we have a similar issue. We are still doing "software
handshaking" between multiple frontends (15 which read data, and 16th
with direct accessto the trigger logic), and we apply a time stamp
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23 Mar 2006, Sergio Ballestrero, Info, svn@savannah.psi.ch down ?
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Hi,
I was trying to update the checkout of Midas, but it looks like something is not
working - maybe a component of the Savannah system:
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26 Mar 2006, Stefan Ritt, Info, svn@savannah.psi.ch down ?
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> Hi,
> I was trying to update the checkout of Midas, but it looks like something is not
> working - maybe a component of the Savannah system:
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27 Mar 2006, Sergio Ballestrero, Info, svn@savannah.psi.ch down ?
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> I just tried now and it seemed to work fine. Do you still have the problem?
>
> - Stefan
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13 Jun 2006, Stefan Ritt, Info, ZLIB dependency modified
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Due to recent problems with the ROME analyzer having zlib.h both in the
system and in the midas tree it has been decided to change the zlib policy in midas. By default, zlib support is not included in the midas analyzer. If
one want it (but I guess only very few experiments need that), one can do a
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13 Jun 2006, Stefan Ritt, Info, Scheduler changed for slow control equipment
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The schedule in mfe.c is used both for "normal" front-ends and for "slow-control" front-ends. Unfortunately it was only optimized for the first class. This
lead to the fact that the slow control equipment was read out at different speed depending if the run is started or not. Furthermore, the maximum readout
speed was somehow limited. This has been changed in the current version of mfe.c (SVN revision 3146). There are now two ways to control the readout speed |
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07 Aug 2006, Stefan Ritt, Info, New multi-threaded midas slow control system
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[b]Multi-threaded slow control system[/b]
The Midas slow control system has been modified to support multi-threaded slow control front-ends. Each device gets it's own thread in the front-end, which |
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11 Feb 2007, Konstantin Olchanski, Info, svn and "make indent" trashed my svn checkout tree...
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Fuming, fuming, fuming.
The combination of "make indent" and "svn update" completely trashed my work copy of midas. Half of
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15 Feb 2007, Ryu Sawada, Info, Latest FC5 Compilation attempt
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On February 13, 2007, gcc 4.1.2 was released.
I checked this version, and it compiles midas successfully,
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23 Feb 2007, Konstantin Olchanski, Info, RFC- support for writing to removable hard disk storage
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At triumf, we are developing a system to use removable hard drives to store data collected by midas
daq stations. The basic idea is to replace storage on 300 GB DLT tapes with storage on removable
esata, usb2 or firewire 750 GB hard drives.
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23 Feb 2007, Konstantin Olchanski, Info, RFC- history system improvements
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While running the ALPHA experiment at CERN, we stressed and broke the MIDAS history system. We
generated about 0.5 GB of history data per day, and this killed the performance of the history plot
system in mhttpd - we had to wait for *minutes* to look at any plots of any variables.
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23 Feb 2007, John M O'Donnell, Info, RFC- support for writing to removable hard disk storage
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We stopped using tapes at Los Alamos a while ago. The model we use is:
write data with mlogger to a local RAID system. This is NFS mounted read only on teh analysis machines, and
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26 Feb 2007, Stefan Ritt, Info, RFC- history system improvements
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I agree to what you propose. I'm pretty sure you are right in getting a significant improvement in readout speed
of the history system. So far there was no big request for improving the history system, since the performance in
the experiments I was involved in was good. In MEG for example, we have ~20MB of history data per day, and all
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26 Feb 2007, Stefan Ritt, Info, RFC- support for writing to removable hard disk storage
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In the MEG experiment, we simply installed 100TB of RAID disks and don't need to change anything ;)
But seriously, you are right that such a system might be beneficial. I propose to extend the current logger code to switch disks. In the current tr_start() |
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26 Feb 2007, Stefan Ritt, Info, Usage of event channel for improved throughput
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Starting from SVN revision 3642, sending events from the front-end has been revised.
Since long time ago, there is a special TCP socket established between any front-end and the mserver which can be used to bypass the midas RPC layer completely |
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26 Feb 2007, Stefan Ritt, Info, Fragmented polled events
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Fragmented polled events have been implemented in SVN revision 3625.
Fragmentation is a method of breaking down large (>MB) events into smaller
pieces and send them through the shared memory buffers, reassembling them at the
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06 Mar 2007, Konstantin Olchanski, Info, commited mhttpd fixes & improvements
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I commited the mhttpd fixes and improvements to the history code accumulated while running the ALPHA
experiment at CERN:
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