> -----Original Message----- > From: centos-bounces at centos.org > [mailto:centos-bounces at centos.org] On Behalf Of DamianS > Sent: Tuesday, February 27, 2007 1:59 AM > To: CentOS mailing list > Subject: Re: [CentOS] Swap Considerations > > On Tue, 2007-02-27 at 07:36 +0200, Alvin Chang wrote: > > On 27/02/07, Feizhou <feizhou at graffiti.net> wrote: > > > When I get firefox and thunderbird fired up, memory usage > can go through > > > the roof so I have allocated 2GB (maximum swap partition > size btw) for > > Pardon me, but I just set up a CentOS box with 8GB of swap partition > > yesterday. Am I misisng something? > > Not really. 2GB is (or was) the maximum _safe_ swap partition size. > However, I have a system with a 4GB swap part and one with a 3GB swap > running CentOS, and they both run fine. > > I have heard however, that smaller-sized swap partitions are > faster/more > efficient. ie. 3x1 GB swap partitions are 'supposed to be' > better than 1 > x 3 GB partition. > So when I'm building new systems, I create a number of 1 GB swap > partitions depending upon predicted load, and give them differing > priorities. > > I've theorized (but never bothered to do some benchmarking or to put > into practice) that optimum swap strategy may be to have varying sizes > eg. 512 MB with highest priority, then 1 GB, 2 GB and 4GB with lowest > priority. > But I think that would be 'gilding the lily', for just a 'theoretical' > increase in eficiency, as opposed to making a practical difference. If you have 4 1GB swap partitions of equal priority it will interleave operations between them giving you a RAID0 type effect and increasing overall swap performance. If you setup swap on top of RAID-1, say with LVM, then this scenario will give you the best performance and be able to continue running in the event of a drive failure. -Ross ______________________________________________________________________ This e-mail, and any attachments thereto, is intended only for use by the addressee(s) named herein and may contain legally privileged and/or confidential information. If you are not the intended recipient of this e-mail, you are hereby notified that any dissemination, distribution or copying of this e-mail, and any attachments thereto, is strictly prohibited. If you have received this e-mail in error, please immediately notify the sender and permanently delete the original and any copy or printout thereof.