4,737 reputation
11034
bio website mattdm.org
location Somerville, MA
age
visits member for 3 years, 10 months
seen yesterday

I'm the Fedora Project Leader. I work for Red Hat — and for the Fedora community at large! – but my posts here are all my own.

Previously, I was a sysadmin in the Academic Computing group at Harvard School of Engineering and Applied Sciences, and before that, I made Boston University Linux.


Jul
30
comment How do you upgrade PHP 5.1 to PHP 5.3 using yum on CentOS
This is not necessary, and also has some disturbing repercussions. For one, now you've not got an easy source for updates for php, and while php is better than it was for a while there, php is generally something you want to stay on top of security patches for.
Jul
30
comment How do you upgrade PHP 5.1 to PHP 5.3 using yum on CentOS
possible duplicate of How do I install php 5.3 on CentOS?
Jun
3
comment How do I see how quickly items are dropping out of memcache?
Oh I see. Not telnet to the server system; use telnet to open a tcp connection to the server port.
Apr
25
comment What is a “Cloud Provider”?
possible duplicate of What is "Cloud Computing"?
Apr
25
comment What is cloud computing?
possible duplicate of What is "Cloud Computing"?
Apr
22
comment awstats password protection
Have you followed what the message said and checked the AWStats documentation?
Apr
7
comment Moving/Adding Additional Swap Location - Redhat 5
Are you sure that swap is filling up /, and not temporary files (or log files, or something else)?
Apr
7
comment Moving/Adding Additional Swap Location - Redhat 5
@rkalajian — look at man swapon for how to set the relative priority of your swap devices. (This can go in fstab, too.)
Apr
7
comment Moving/Adding Additional Swap Location - Redhat 5
You can also use files; you don't have to use partitions, and you don't have to use something like swapd to do so.
Mar
31
comment How do I install PHP 5.3 on CentOS?
Yeah. :( lwn.net/Articles/435744
Mar
9
comment How can I disconnect ssh users, or limit the number of ssh logins?
There's always the "If you are caught logging in from two places simultaneously, there will be consequences." approach.
Mar
9
comment How can I disconnect ssh users, or limit the number of ssh logins?
@mmr — cryptographic tokens are a good way to deal with that. :)
Mar
9
comment MPM Prefork, too many apache2 process?
@yes123: if you're hitting the suggestion to raise MaxClients and you're already at the reasonable limit for your server size, you need more RAM.
Mar
9
comment MPM Prefork, too many apache2 process?
@yes123: don't worry about the virt usage — sorry for stressing you out about that yesterday; I was being a little overzealous and should have caught that. It's the RSS that is closest to meaningful and what you should size the maxservers/maxclients setting by.
Mar
9
comment MPM Prefork, too many apache2 process?
@yes123: you just never got the traffic to fire them all up. It's definitely the problem. If requests overcome that limit, people will have to wait. But that's a lot of requests — you say your longest php script takes 0.09 seconds to load, so worst case each one can handle 11 requests a second. Are you really likely to serve over 3000 requests a second? And if you are, can the CPU keep up with that? If you're hitting that problem, you need a bigger box.
Mar
9
comment MPM Prefork, too many apache2 process?
@yes123: that's okay. So, 4GB/13 gives you a server limit of roughly 300.
Mar
9
comment MPM Prefork, too many apache2 process?
@yes123: but what is the per-process size now?
Mar
9
comment MPM Prefork, too many apache2 process?
@yes123: are your apache2 processes now each smaller, or are you seeing them at size 185MB again?
Mar
9
comment MPM Prefork, too many apache2 process?
@yes123: you can call it offtopic, or you can call it "I'm trying to help you nail down your problem". If the phpinfo is showing that limit yet the processes are still huge, either PHP is showing you unhelpful information or something other than PHP is eating memory. Unless you have an idea of what that might be, narrowing down the problem is the only rational approach.
Mar
9
comment MPM Prefork, too many apache2 process?
@yes123 — can you humor me and set it globally? (And check your codebase for any code which raises the limit.) If that's still not working, can you try disabling PHP entirely temporarily and observing the size of the apache worker processes?