Re: Future of Qmail-LDAP

Hi Hugo,

Thanks for your prompt reply.
The problem was CPU load not I/O in my tests and case.

Number of users is not important. I tested it 5-6 months ago but test
sceneria is very simple.
1. Install netqmail
2. run tcpserver with 700 connection limit (tcpserver -c 700) and disable
rbl any other IP level checks
3. configure xstress tool (http://xstress.sourceforge.net/) to open 600
concurrent connection and only one mail every connection.
4. run xstress tool two or three time,

You will  see high cpu load(even in first test).
The hardware  configuration has no big impact in this tests. I tried
different configurations(soft raid/hard raid, SAS/SCSI, dual core/quad core
CPU)
I also tried to put qmail queue on ramdisk to isolate I/O, the result was
same! the load is still higher than 50

Make same tests with postfix on the same server. the load will not be bigger
than 2-3

PS: I am stil using qmail :) and would like to continue using.


On Wed, Feb 3, 2010 at 2:25 PM, Hugo Monteiro <[email protected]>wrote:

> On 02/03/2010 12:03 PM, Ibrahim Harrani wrote:
>
>> Hi Hugo,
>>
>> I have some problems with qmail-smtpd high load under many concurrent
>> connection.
>> I also stated details at http://marc.info/?l=qmail&m=126515210427322&w=2<
>> http://marc.info/?l=qmail&m=126515210427322&w=2>
>>
>> Postfix handles big concurrent connections very well in SMTP level.
>> As you know, more than %60-70 of spams are dropped at smtp level via RBL,
>> rcpt verification and greylisting. so smtpd service performance is very
>> important.
>>
>> If there is a  way to daemonize qmail smtpd processes or to fix of this
>> issue, I belive that qmail will be more faster.
>>
>> Any idea?
>>
>>
>
> Hello Ibrahim,
>
> The load that you observe, where does it come from.. raw processor chewing
> or I/O?
>
> Have you seen qmail-smtpd processes consuming huge ammounts of CPU?
>
> Are you using an alternate qmail-queue? Is that alternate qmail-queue
> process responsible for eating all your CPU?
>
> Are you sure all the RBLs you're consulting are replying in time?
>
> Mind if i ask how many user accounts and an estimate on the amount of
> accepted messages per day?
>
>
> Regards,
>
> Hugo Monteiro.
>
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