default_destination_concurrency_limit and zimbraLmtpNumThreads

[zhangyq]

I want to modify the value of these two attributes :default_destination_concurrency_limit and zimbraLmtpNumThreads
Somebody who knows the maxmum of them ? And once increased them to the maxmum , what will happen to the server . My aim is to speed up the servers. because our users compliant that it cost quite a long time to receive the new mails. somebody know ? thanks!

[uxbod]

Is that definitely the issue why emails are being processed slowly ? Are you that it is now within Amavisd where the problem is eg. slow AV and AS checks. Is this a default installation, or have you changed the SA rules or RBLs ?

I would also help if we knew which version of ZCS you were running ?

su - zimbra
zmcontrol -v

[zhangyq]

I am not very sure whether or not is the problem of these two attributes .but i still want to have a try. I now want to know the maxmum of them .and the risk of what i am doing .thanks!

[uxbod]

Have a read of Performance Tuning Guidelines for Large Deployments - Zimbra :: Wiki especially the section on LMTP.

[zhangyq]

I read the file ,but i still not found the maxmum. do you know ?

[uxbod]

Maximum would be dependant on TCP kernel parameters and the spec of you server as each connection would also use CPU cycles and memory. Personally I would be looking to other areas of your system than these two values. What does top and free show ?