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<DIV><SPAN class=155330507-06022007>We have a need to create a very small GFS
filesystem, as low as on a 512MB disk partition. For a three node cluster (
-j 3) what is the suggested value for Journal size and ResourceGroup size?
Obviously I want maximize the usable diskspace while still keeping it safe to
operate and get a decent performance.</SPAN></DIV>
<DIV><SPAN class=155330507-06022007></SPAN> </DIV>
<DIV><SPAN class=155330507-06022007>The default gfs_mkfs only leaves about 110 /
512MB volume. </SPAN><SPAN class=155330507-06022007>Reducing the Journal
size from 128M(default) to 32M(min) gives me back about
288MB. </SPAN><SPAN class=155330507-06022007></DIV></SPAN>
<DIV><SPAN class=155330507-06022007><BR>What is the impact of reducing journal
size? Can I safely live with this journal size if my app using this filesystem
is less metadata intensive?</SPAN></DIV>
<DIV><SPAN class=155330507-06022007></SPAN> </DIV>
<DIV><SPAN class=155330507-06022007>Similarly w.r.t ResourceGroup size,
what is the impact of reducing its size from 128M (default) to 32M (min)
?</SPAN></DIV>
<DIV><SPAN class=155330507-06022007> </DIV></SPAN>
<DIV><SPAN class=155330507-06022007>Appreciate any thoughts on
this.</SPAN></DIV>
<DIV><SPAN class=155330507-06022007></SPAN> </DIV>
<DIV><SPAN class=155330507-06022007>thanks,</SPAN></DIV>
<DIV><SPAN class=155330507-06022007>Sridharan</SPAN></DIV>
<DIV><SPAN class=155330507-06022007></SPAN> </DIV>
<DIV><SPAN class=155330507-06022007></SPAN> </DIV>
<DIV><SPAN class=155330507-06022007>PS: Few of those gfs_mkfs snippets for
reference,</SPAN></DIV>
<DIV><SPAN class=155330507-06022007></SPAN> </DIV>
<DIV><SPAN class=155330507-06022007>
<DIV><SPAN class=155330507-06022007>$ gfs_mkfs -p lock_dlm -t alpha:gfs2 -j 3
/dev/hda12</SPAN></DIV>
<DIV><SPAN class=155330507-06022007>...</SPAN></DIV>
<DIV><SPAN
class=155330507-06022007>Blocksize:
4096<BR>Filesystem
Size: 28164<BR>Journals:
3<BR>Resource Groups: 8</SPAN></DIV>
<DIV><SPAN class=155330507-06022007></SPAN> </DIV></SPAN></DIV>
<DIV><SPAN class=155330507-06022007>
<DIV><SPAN class=155330507-06022007>$ gfs_mkfs -p lock_dlm -t alpha:gfs2 -j 3 -J
32 /dev/hda12</SPAN></DIV>
<DIV><SPAN class=155330507-06022007>...</SPAN></DIV>
<DIV><SPAN
class=155330507-06022007>Blocksize:
4096<BR>Filesystem
Size: 101892<BR>Journals:
3<BR>Resource Groups: 8<BR></SPAN></DIV>
<DIV><SPAN class=155330507-06022007>$ gfs_mkfs -p lock_dlm -t cisco:gfs2 -j 3 -J
32 -r 32 /dev/hda12</SPAN></DIV>
<DIV><SPAN class=155330507-06022007>...</SPAN></DIV>
<DIV><SPAN
class=155330507-06022007>Blocksize:
4096<BR>Filesystem
Size: 101868<BR>Journals:
3<BR>Resource Groups: 14</SPAN></DIV>
<DIV><SPAN class=155330507-06022007></SPAN> </DIV>
<DIV><SPAN
class=155330507-06022007></SPAN> </DIV></SPAN></DIV></BODY></HTML>