Hi Moloko,

We made the experience that you cannot compare the load averages directly
between Intel an Linux/390. Also the shown load average on our linuxes is
higher using a 2.4 kernel as with kernel 2.2.x (why?)

But if there's really a problem with the performance on the S390 you have to
find out where your bottleneck is. On our smtp-relay on the z900 (under VM,
SuSE7.0 with kernel 2.4.7, sendmail 8.11) the disk performance slowed down
the system and pushed up the load average. A solution is to attach the disks
using more channels and to stripe the spool-area over several disks and
channels with LVM or software Raid0.

Sendmail also slows down if the number of mails in your spooldir gets to
high. So if you have a huge amount of spooled mails it is better to split
the spool area in several subdirs with dedicated sendmail instances
processing the queues.

We also had bad performance with kernel 2.2.x.

Robert.



----- Original Message -----
From: "Moloko Monyepao" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Tuesday, April 23, 2002 3:35 PM
Subject: Sendmail Perfomance


I have sendmail 8.11.6-3 installed on Redhat 7.2 (server installation) on
S390(Lpar) with an IFL dedicated to this Lpar. We made the  O QueueLA=10 and
the O RefuseLA=12 which is the same setup as on my Intel machine. When using
top to check the load the following is what I get. The O
MaxDaemonChildren=100 on S390 and 300 on Intel.

Intel Machine = The Load average does not go over 10% when setup for both
incoming and outgoing mail.

S390 Machine = The Load average goes to more than 10% and it start rejecting
connections if we set it up for both incoming and outgoing mail and it gets
up to about 6 to 8% if we only set it up for outgoing mail which is not a
lot.

Please assist
Moloko

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