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Entry  20 Sep 2006, Stefan Ritt, Suggestion, Increase of maximum event size 
    Reply  20 Sep 2006, Stefan Ritt, Suggestion, Increase of maximum event size 
    Reply  27 Sep 2006, Konstantin Olchanski, Suggestion, Increase of maximum event size 
       Reply  28 Sep 2006, Stefan Ritt, Suggestion, Increase of maximum event size 
Message ID: 302     Entry time: 20 Sep 2006     Reply to this: 303   308
Author: Stefan Ritt 
Topic: Suggestion 
Subject: Increase of maximum event size 
Dear midas users,

The current event size in midas is limited to 512k (MAX_EVENT_SIZE in midas.h). This is mainly due to old (pre 2.2) linux kernels which had only a very limited shared memory pool. These days this limit has increased considerably and I question if we should increase the default event size and to which size we should increase it.

The drawback of a larger event size is that the SYSTEM event buffer has to hold at least two events, and when the last midas program is stopped or started, this buffer has to be written to or read from the .SYSTEM.SHM file, which slows down the start/stop of the program. But writing/reading a few MB is fast these days anyhow so this again might now be a big problem. So what do you think how big we should make the default max event size?

- Stefan
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