LISTSERV mailing list manager LISTSERV 16.0

Help for LINUX-L Archives


LINUX-L Archives

LINUX-L Archives


LINUX-L@LISTS.UFL.EDU


View:

Message:

[

First

|

Previous

|

Next

|

Last

]

By Topic:

[

First

|

Previous

|

Next

|

Last

]

By Author:

[

First

|

Previous

|

Next

|

Last

]

Font:

Monospaced Font

LISTSERV Archives

LISTSERV Archives

LINUX-L Home

LINUX-L Home

LINUX-L  2007

LINUX-L 2007

Subject:

Re: /dev/shm

From:

Doug Goldstein <[log in to unmask]>

Reply-To:

Platform Independent Linux List! <[log in to unmask]>

Date:

Fri, 9 Mar 2007 20:22:55 -0500

Content-Type:

text/plain

Parts/Attachments:

Parts/Attachments

text/plain (48 lines)

Arthur Sherman wrote:
> Hi,
>
> I have a server with 3GB RAM running
> sendmail/dovecot/bind/apache/proftpd/Mailscanner/SpamAssassin/antivirus @
> CentOS-4.4.x86, hosting several domains.
>
> There are these lines in /etc/fstab:
> none /dev/shm tmpfs noexec,nosuid,rw
> 0 0
> none /var/spool/MailScanner/incoming tmpfs defaults 0 0
>
> 'df -h' shows that /dev/shm takes 50% of RAM, while there are actually some
> Kbytes there:
> Filesystem Size Used Avail Use% Mounted on
> none 1.5G 28K 1.5G 1% /var/spool/MailScanner/incoming
>
> My questions:
> 1) how can I make /dev/shm smaller, say 512MB? I believe it will be more
> than sufficient for Mailscanner.
> 2) what else can I make run from /dev/shm to gain performance?
>
> Thanks!
>
I think you're misunderstanding the entire /dev/shm and tmpfs.

tmpfs is a filesystem that is suppose to live entirely in memory,
whether that be RAM or swap it doesn't matter. Specifying a size
parameter and the df -h output to a tmpfs will appear to be very
misleading, the kernel will actually not consume that amount, that is
essentially the maximum amount of size that the tmpfs can take up.

Now /dev/shm on the other hand is just a location of shared memory. You
commonly see it implemented as a tmpfs, however it does not necessarily
have to be. It's basically just a shared memory segment that processes
can share data between.

>
>
> Best,
>
> --
> Arthur Sherman
>
> +972-52-4878851
> CPTeam
>
>

Top of Message | Previous Page | Permalink

Advanced Options


Options

Log In

Log In

Get Password

Get Password


Search Archives

Search Archives


Subscribe or Unsubscribe

Subscribe or Unsubscribe


Archives

2020
2019
2018
2017
2016
2015
2014
2013
2012
2011
2010
2009
2008
2007
2006
2005
2004
2003
2002
2001
2000
1999
1998
1997

ATOM RSS1 RSS2



LISTS.UFL.EDU

CataList Email List Search Powered by the LISTSERV Email List Manager