Yes to both. First I would make sure that the watchdog table is InnoDB as that will help, especially on table locks. Another option is to hijack the dblog module and create your own from it. Basically just copy, rename what needs renamed (hooks, etc) and in hook_watchdog filter out the things you really don't need written to the database. Even better is replacing the storage for the watchdog with something like MongoDB, sqlite or even plain old log files.

An option on the email is to setup something like Google Apps or any external email service for handling the emails, then use the SMTP module to send all the emails through Google Apps. This saves some decent load on the server since sendmail isn't fired for each email.

(FYI - from a consultant stand point I always recommend Google Apps to sites unless they have a ton of email addresses. It greatly reduces the headache of handling email and gives the users an interface that most of them are probably use to. I even use it for my own company. Every client I have switched to it has been thrilled.)

Jamie Holly
http://www.intoxination.net 
http://www.hollyit.net

On 11/5/2011 10:44 AM, Ms. Nancy Wichmann wrote:

I've been asked questions about a site that slows way down on occasion. This is a cloud-based server at Rackspace. Since Rackspace has a fairly good reputation, I am guessing they are not the real problem.

I looked at the database stats; it is using Qcache and the numbers look pretty decent.

What I do see that I question is that their notifications module (I forget which one):

A) Writes to dblog (Watchdog) on every cron interval, even if it has nothing to do (I hate that).

B) When there is a notification (pretty often), it writes a separate line for each one.

C) Some of those notifications result in many (100 or more) emails. During one page refresh when I experienced the drastic slow down, this high volume email happened.

So I am wondering if these high-volume email sends can have a serious effect on performance? Since I assume the answer is yes, what can be done to lessen this impact? I see two main spots to work on: Watchdog usage and email load.

Nancy

Injustice anywhere is a threat to justice everywhere. -- Dr. Martin L. King, Jr.