New MS install is slow to an extreme, was: reducing MailScanner memory footprint, was: ClamAV 0.93 released

DAve dave.list at
Thu May 22 19:41:35 IST 2008

Richard Siddall wrote:
> DAve wrote:
>> While we, I, made the newb mistake of upgrading everything including 
>> OS in one fell swoop the main issue has been identified. Last night we 
>> shutdown clamavmodule and started up clamd. A picture is worth a 
>> thousand words.
> Wow, big difference.  I can't think why using the daemon would be faster 
> than using a linked in library other than that the higher memory 
> footprint with clamavmodule might be pushing you over a limit and the 
> server was swapping.  Presumably there was no indication of that.

No swapping. Using clamavmodule raised each MS child over 100mb each. 
Using clamd each MS child runs at only 60k. MS was reporting Virus 
processing speeds with clamavmodule in the 1200 to 5000 bytes per second 
range, with clamd we are seeing 66,000 bytes per second.

Kernel tuning, disk tuning, Sendmail tuning, all helped to some extent, 
but clamd made an amazing change. We are handling 30% more mail now than 
a year ago and with considerable less load reported.

We will see if today's performance continues.


In 50 years, our descendants will look back on the early years
of the internet, and much like we now look back on men with
rockets on their back and feathers glued to their arms, marvel
that we had the intelligence to wipe the drool from our chins.

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