Hi, I'm going to set up a new storage for our email users (about 10k). It's a network attached storage (Coraid). In your opinion, what is the best file system for mail server (pop3/imap/webmail) purpose? Thank you
On 12/01/2014 11:24 AM, absolutely_free at libero.it wrote:> Hi, > I'm going to set up a new storage for our email users (about 10k). > It's a network attached storage (Coraid). > In your opinion, what is the best file system for mail server (pop3/imap/webmail) purpose? > Thank youThis thread (and others) has covered some options http://www.dovecot.org/list/dovecot/2013-May/090041.html About XFS, it's worth noting that it doesn't come with a version number, so XFS in a recent kernel simply doesn't mean the same thing as an older kernel. You kind of need to look at the kernel version instead of an "XFS version". Also, the devil will be in the details. You'll always need to worry about things like alignment etc., particulars of your configuration / work load. You really can't look at it as simply a question of which filesystem to choose.
Il 01/12/2014 17:24, absolutely_free at libero.it ha scritto:> Hi, > I'm going to set up a new storage for our email users (about 10k). > It's a network attached storage (Coraid). > In your opinion, what is the best file system for mail server (pop3/imap/webmail) purpose? > Thank youHi, XFS, if you can use RHEL/CentOS 6, ext4 with others distro. I used XFS (with 20k users) until I switched to a NetApp (and now I'm really happy). Ciao
> I used XFS (with 20k users) until I switched to a NetApp (and now I'm > really happy).Yes, I'd say NetApp is pretty good, we are using this type of storage at work. Regards -- CHUNKZ.NET - casual fiddler and computer technician Bertrand Caplet, Flers (FR) Feel free to send encrypted/signed messages Key ID: FF395BD9 GPG FP: DE10 73FD 17EB 5544 A491 B385 1EDA 35DC FF39 5BD9 -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: OpenPGP digital signature URL: <http://dovecot.org/pipermail/dovecot/attachments/20141201/36aafefc/attachment.sig>
> On 01 Dec 2014, at 18:24, absolutely_free at libero.it wrote: > > Hi, > I'm going to set up a new storage for our email users (about 10k). > It's a network attached storage (Coraid). > In your opinion, what is the best file system for mail server (pop3/imap/webmail) purpose?Depends on what OS you have chosen, or if OS is not the limiter I would go with ZFS. Sami
W dniu 2014-12-01 o 18:19, Alessio Cecchi pisze:> > Il 01/12/2014 17:24, absolutely_free at libero.it ha scritto: >> Hi, >> I'm going to set up a new storage for our email users (about 10k). >> It's a network attached storage (Coraid). >> In your opinion, what is the best file system for mail server >> (pop3/imap/webmail) purpose? >> Thank you > Hi, > > XFS, if you can use RHEL/CentOS 6, ext4 with others distro.Hi! Does XFS works better on RHEL than on others distro?;)
Am 01.12.2014 um 17:24 schrieb absolutely_free at libero.it:> Hi, > I'm going to set up a new storage for our email users (about 10k). > It's a network attached storage (Coraid). > In your opinion, what is the best file system for mail server (pop3/imap/webmail) purpose? > Thank youIf it is a NAS, as you state, then you don't have to think about the filesystem, because the storage unit does not provide block devices for filesystem creation. Else - in case you get block storage instead of NAS - "best filesystem" depends on a lot of parameters. If there would be a best one, then there wouldn't be room for several choices. Alexander
El 01/12/14 a las 18:45, Sami Ketola escribi?:> >> On 01 Dec 2014, at 18:24, absolutely_free at libero.it wrote: >> >> Hi, >> I'm going to set up a new storage for our email users (about 10k). >> It's a network attached storage (Coraid). >> In your opinion, what is the best file system for mail server (pop3/imap/webmail) purpose? > > Depends on what OS you have chosen, or if OS is not the limiter I would go with ZFS. >Have you any performance comparison with xfs? I'm running two imap servers. One with about 9k accounts and 3.5TB of storage, and another with 55k accounts and 2TB of storage with XFS, and I'm thinking about migrating them from XFS to ZFS but I'm concern about IO performance of ZFS. When we developed these two servers, I remember reading some zfs performance problems in comparison with xfs (I have lost the link) and that was the reason to finally use xfs, but now we are having problems with LVM snapshots and we also like some zfs features (like replication) so we are thinking about the change. -- Angel L. Mateo Mart?nez Secci?n de Telem?tica ?rea de Tecnolog?as de la Informaci?n y las Comunicaciones Aplicadas (ATICA) http://www.um.es/atica Tfo: 868887590 Fax: 868888337
El 01/12/14 a las 17:24, absolutely_free at libero.it escribi?:> Hi, > I'm going to set up a new storage for our email users (about 10k). > It's a network attached storage (Coraid). > In your opinion, what is the best file system for mail server (pop3/imap/webmail) purpose? > Thank you >And another related question... Does anybody of you have any experience with distributed filesystems like lustre or ceph? How is the performance of them in comparison with "legacy" filesystems like xfs? -- Angel L. Mateo Mart?nez Secci?n de Telem?tica ?rea de Tecnolog?as de la Informaci?n y las Comunicaciones Aplicadas (ATICA) http://www.um.es/atica Tfo: 868887590 Fax: 868888337
Am 01.12.2014 um 17:24 schrieb absolutely_free at libero.it:> I'm going to set up a new storage for our email users (about 10k). > It's a network attached storage (Coraid). > In your opinion, what is the best file system for mail server (pop3/imap/webmail) purpose?It depends on how conservative you are. Btrfs won't cut it, because too slow and still too much experimental. ZFS on Linux is being maintained outside the kernel and eats up memory like a horde of cockroaches. So this is also for most no viable choice. This brings down either ext4 or XFS. Both file systems have a decade old code base and are quite mature. If you need the ability to shrink a file system, it's ext4. If you are on the conservative side, it's also quite ext4. If you are feeling a little bit more adventurous, it's XFS. Note that XFS had some serious bottle necks in writing to its journal which have been solved in kernel 3.3. XFS is kinda a somewhat difficult topic; some people love it and have no problems with it at all, while other people say they've seen serious problems with it. There's been for example a talk by Peer Heinlein on Linux Tag 2012, where he gave us his insights about migrating his mail user base (> 100.000 accounts on roughly 12 TB storage) away from Maildir to mdbox. He told there that he had seen at least three cases of XFS failure and therefore he considers it unreliable; he switched from ext3 to ext4.
On 18/12/2014 08:57, Marc Stuermer wrote:> ZFS on Linux is being maintained outside the kernel and eats up memory > like a horde of cockroaches. So this is also for most no viable choice.I can't speak for ZFS on Linux but the subject is "best file system?" not "best file system for Linux?". ZFS uses spare RAM but does not "eat" it. I have a system here with 64GB RAM and 48GB is being used by ZFS. It's only using RAM that is otherwise unused and if my file system were not using 48GB RAM it would be wasted. It's not taking RAM from programs and if I ask for RAM the amount used by ZFS reduces. The system has an amount of a free RAM and in timing tests I can not perceive any difference in taking RAM from the free buffer or when the amount requested is large enough to require ZFS to give some up. I also have ZFS on a 12 year old Celeron laptop with 1G RAM and it runs without any problems. That ZFS needs a lot of RAM or CPU is false. "zfs set -o compress=gzip" works wonders for mail storage.