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<DIV dir=ltr align=left><SPAN class=823183115-17022011><FONT color=#0000ff
size=2 face=Verdana>This iowait thing is driving me batty. The system was
running fine for a long time at about 1-7% iowait except during backups. During
backups iowait is usually pegged at 25%. But recently, the system has started
running at 25% iowait <U>all the time</U>, with periods of 50% iowait and peaks
of 70-90%. This is a relatively sudden development.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=823183115-17022011><FONT color=#0000ff
size=2 face=Verdana></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=823183115-17022011><FONT color=#0000ff
size=2 face=Verdana>The server is 4-core PowerEdge 2950 with 8GB of RAM and
6x300GB 7.5K SAS drives in a RAID 5 array. All it does is FTP. It peaks at about
250 concurrent FTP users. Average file size is about 80K. The backing device for
drbd0 is a 2TB LVM partition. The filesystem is ext3. Since kjournald is the
biggest consumer of disk iops, I will soon change the filesystem to mount with
'noatime'. </FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=823183115-17022011><FONT color=#0000ff
size=2 face=Verdana></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=823183115-17022011><FONT color=#0000ff
size=2 face=Verdana>Any ideas? Is there something about using LVM+drbd+ext3 with
a 2TB partition (1.3TB used) that causes a sudden jump
in disk wait? </FONT></SPAN></DIV>
<DIV> </DIV>
<P style="MARGIN: 0in 0in 0pt" class=MsoNormal align=left><SPAN
style="FONT-FAMILY: Tahoma; FONT-SIZE: 10pt"><FONT
face=verdana>--<BR></FONT></SPAN><SPAN
style="FONT-FAMILY: Tahoma; FONT-SIZE: 10pt"><FONT face=verdana>Eric
Robinson<BR></FONT></SPAN></P>
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color=#0000ff></FONT> </P></FONT></SPAN><BR><BR><FONT color=silver><SPAN style="FONT-SIZE: 7.5pt; COLOR: gray; FONT-FAMILY: Verdana"><FONT size=1>Disclaimer - February 17, 2011</FONT></FONT></SPAN></FONT> <P></P><FONT size=1><FONT face=Verdana color=gray><SPAN style="FONT-SIZE: 7.5pt; COLOR: gray; FONT-FAMILY: Verdana">This email and any files <FONT size=1>transmitted</FONT> with it are confidential and intended solely for <STRONG>drbd-user@lists.linbit.com</STRONG></SPAN></FONT><FONT face=Verdana color=gray><SPAN style="FONT-SIZE: 7.5pt; COLOR: gray; FONT-FAMILY: Verdana">. If you are not the named addressee you should not disseminate, distribute, copy or alter this email. Any views or opinions presented in this email are solely those of the author and might not represent those of Physicians' Managed Care or Physician Select Management. Warning: Although Physicians' Managed Care or Physician Select Management has taken reasonable precautions to ensure no viruses are present in this email, the company cannot accept responsibility for any loss or damage arising from the use of this email or attachments.</SPAN></FONT></FONT></BODY></HTML>