[rt-users] Re: Performance Issues

[Bob Goldstein]

>Ruslan U. Zakirov <cubic at acronis.ru> wrote:
>> 
>> Guys. Please. Fill this info on wiki.bestpractical.com with descriptions 
>> and may be links to archive of this or other similar discussion.
>> 
>> '-processes X' is not optional record in config but required IMHO. When 
>> you run only _one_ FastCGI process then it's something like running RT 
>> under mod_perl in 'httpd -X' mode.
>
>Another data point: this helped us greatly.  I added the following to the
>FastCGIFAQ page, and changed the examples below to match -- can someone
>fact-check me please?
>
>    Q: Why is RT under FastCGI so sloooooooow? When using a progressive-rendin
>g
>    browser like Firefox I see the entries appear slowly, one at a time, but
>    the server doesn't appear to be overloaded and the database is not large.
>
>    A: You might only have spawned one mason_handler.fcgi, which would cause
>    all the httpd processes to block, waiting for it to service them. Make sur
>e
>    you use an appropriate "-processes X" option in your FastCgiServer
>    directive, as shown below. You should have as many mason_handler.fcgi
>    processes as the nominal number of httpds that are usually running
>    (StartServers <= "-processes" <= MaxSpareServers) 
>

    Are you sure about your recommended number of processes? My
    understanding is that apache spawns StartServers processes
    when it launches, and that it continues to spawn processes,
    keeping between MinSpareServices and MaxSpareServers idle,
    just to handle any unanticipated surge. It's quite possible
    to have MaxSpareServers=10, yet to have 100 running processes
    on a loaded server.

    Too many fcgi processes would eat memory, too few won't perform.

    I also have a question about your explantion.  I think it's
    true that if my request is being processed by the only
    fcgi process, yours will block until mine is complete.
    But why would my request, once processing starts, be slow?
    I would have thought the symptom would be a long latency
    followed by a fast full page.

        bobg