manav wrote:
>
> Hi Mike, Russ,
Hi !
>
> We are running the alpha phase right now (with whatever current
> implementations we have), and I have serious doubts about the stability and
> scalability of the system. The maximum load that I've put on my production
> boxes is 250,000 emails so far and I've had similar issues that I mentioned
> on my development boxes (the ones that are resemble a Beetle, to quote Mike
> :-) ).
Just as an example of the speed of qmail and ezmlm:
Machine: 1U rackmount cheapo 600Mhz Celeron, 128MB RAM, 18GB hard disk
OS: NetBSD 1.5
MTA: Qmail 1.03 with only the verh patch
List Manager: Ezmlm 0.53 with idx 0.40
remoteconcurrency: 120
Here are some stats from the first large mailing with this server. As
you can see, within 15 minutes most of the deliveries were completed.
The only kernel tuning I did was to raise the max processes to 256 and
max open files per process to 512. The numbers look a little off since
there are a few old messages still going through, mostly mail servers
that were previously unreachable.
12.45.21 message sent to 4773 addresses
12.50.00 1738 deliveries
1924 attempts
1761 successes
187 failures
12.55.00 1775 deliveries
1937 attempts
1779 successes
166 failures
13.00.00 423 deliveries
455 attempts
433 successes
32 failures
13.05.00 13 deliveries
14 attempts
13.10.00 2 deliveries
2 attempts
-------------------------------
Total 3951 deliveries
4332 attempts
With the large concurrency patch, this throughput could be increased
significantly. I will put it into use if I get a requirement to send to
at least 10,000 addresses.
Using qmail-ldap and qmqp with a frontend master server and several
slave servers, you can distribute the load among several servers very
easily. For example, if you have 4 slave servers then use a unique
mailhost attribute for each quarter of your subscriber base. The
scalability of qmail-ldap is almost limitless, I think. The master
server will transfer the qmqp messages to the slave servers via qmqp
faster than you can even dream of. For more info, www.nrg4u.com
qmail-ldap homepage.
Regards,
Mike
