> Likely a script problem, httpd wont cause harm
Did some further investigation and it seems APC (php opcode cache) generates
this IO(or so it seems).
http://serverfault.com/questions/361032/high-disk-i-o-when-cache-is-used
> that is pretty ancient
RHEL. Not that ancient.
> ahhhhhhhhhhhhhhh so this is a VM
Yes :p any further point on this?
> If you are not sure what APC is then you cant need it and should disable it
Although I might not have a full understanding of what it does the customer is
using it (passively). So disabling is not an option.
Sometimes disabling stuff from which you don't know what it does backfires ;)
One of these days I will be able to change the setting and verify that this
fixed my problem.
Thanks for your response anyway:)
Grtz
From: noel.but...@ausics.net
To: users@httpd.apache.org
Date: Wed, 16 May 2012 10:12:47 +1000
Subject: Re: [users@httpd] IO load due to apache? Normal httpd behavior or
script related?
On Mon, 2012-05-14 at 17:41 +0200, G VM wrote:
Hi all,
Recently I found out one server generating alot of load on our storage.
Likely a script problem, httpd wont cause harm
Linux 2.6.18-274.7.1.el5
that is pretty ancient
httpd 25431 apache DEL REG 253,3
13 /tmp/apc.Fm8SAS
httpd 25454 apache DEL REG 253,3
13 /tmp/apc.Fm8SAS
httpd 25622 apache DEL REG 253,3
13 /tmp/apc.Fm8SAS
httpd 25792 apache DEL REG 253,3
13 /tmp/apc.Fm8SAS
httpd 25794 apache DEL REG 253,3
13 /tmp/apc.Fm8SAS
httpd 25846 apache DEL REG 253,3
13 /tmp/apc.Fm8SAS
httpd 25849 apache DEL REG 253,3
13 /tmp/apc.Fm8SAS
...
The only other is for sshd and another for vmware tools.
ahhhhhhhhhhhhhhh so this is a VM
If I try to do ls -lh /tmp/apc.Fm8SAS I get no such file or directory.
Using the access time I would see if this file is accessed over and over again.
Am I missing something here? Is this apache doing a fstat() call for
example?
Or is this file created and deleted over and over again at a very fast pace
that I can't access it (this seems less likely to me).
Has anyone seen such behaviour in httpd? Or does someone knows a little
more of the inner workings of httpd?
The name does me think that APC (sort of php module iirc) is having
something to do with this:
apc.ini:apc.mmap_file_mask=/tmp/apc.XXXXXX
The config file seems to confirm this.
If you are not sure what APC is then you cant need it and should disable it
