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Difference between revisions of "Filesystem Policy"

From HLRS Platforms
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Avoid formated I/O on SX, try to do large block, unformated I/O.
 
Avoid formated I/O on SX, try to do large block, unformated I/O.
  
You can use the variables ''F_SETBUF'' and ''C_SETBUF'' to set buffer size
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You can use the variables <tt>F_SETBUF</tt> and <tt>C_SETBUF</tt> to set buffer size
 
of standard buffered I/O.
 
of standard buffered I/O.
  
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you clean that directory at job end!
 
you clean that directory at job end!
  
To copy large files on SX use ''cp -b 32768'': this speeds up the copy by a factor  
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To copy large files on SX use
of 5 vs. the default (''cp -b 1024''), a buffer > 32768 will not work!
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{{Command|command = cp -b 32768 <source> <target>}}
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this speeds up the copy by a factor of 5 vs. the default (<tt>cp -b 1024</tt>), a buffer > 32768 will not work!

Latest revision as of 20:33, 26 February 2010

There is no backup of date. Most important first.

Home filesystem has quotas active, temporary diskspace can be requested through workspace mechanism.

For home and workspace filesystems, best performance is achieved with large I/O in blocks > 4MB. All filestytems can be accessed from SXes and frontends under same path.

Avoid formated I/O on SX, try to do large block, unformated I/O.

You can use the variables F_SETBUF and C_SETBUF to set buffer size of standard buffered I/O.

For fast local I/O, you can create a directory in /raid/tmp, this is a fast node local disk space. Please make sure that you clean that directory at job end!

To copy large files on SX use

cp -b 32768 <source> <target>

this speeds up the copy by a factor of 5 vs. the default (cp -b 1024), a buffer > 32768 will not work!