Date: Tue, 18 Nov 2014 17:29:46 +0000 From: Matthew Seaman <matthew@freebsd.org> To: freebsd-questions@freebsd.org Subject: Re: Hardware RAID or software for ZFS Message-ID: <546B820A.7040806@freebsd.org> In-Reply-To: <7F1B1DC4-46CA-4B96-836B-2D2D494F60E8@todoo.biz> References: <7F1B1DC4-46CA-4B96-836B-2D2D494F60E8@todoo.biz>
next in thread | previous in thread | raw e-mail | index | archive | help
This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --rp1u3UDDiuFjVOxa8Nlv0Ujjwss4mwktP Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 11/18/14 15:28, bsd@todoo.biz wrote: > I would need your help in order to figure out which will be the best in= order to setup a server which will be used as a Poudriere server.=20 >=20 > My question is related to the usage of hardware RAID controller (JBOD) = or software based controller (graid)=20 >=20 > Server we are targeting is a SuperMicro 1018R-WC0R - 1U >=20 > I used to build my server using an HBA such as LSI SAS 9207-8i or LSI S= AS 9201-16i > Then I=E2=80=99ll configure the HBA as JBOD so that disks can be presen= ted correctly to the system so that we can build our ZFS FS on top of tha= t.=20 >=20 >=20 > My sysadmin suggested me to get rid of the HBA and use direct connectiv= ity and Graid.=20 >=20 >=20 > I would like to have some feedback on various aspects :=20 >=20 > 1. performance=20 > 2. usability=20 > 3. problem one might have encountered >=20 OK -- Your sysadmin is correct about the direct connectivity thing, but graid? Seriously? That's an option for really cheap and some might say quite nasty pseudo-raid things you get on some desktop hardware. If you're going to be building a significant number of packages with any regularity, then you're going to need something better than that. The LSI HBAs you suggest are known to work well with FreeBSD. If you're going to be using ZFS -- which is really a no-brainer for a poudriere box, as poudriere has a lot of functionality built around cloning and snapshotting and other things that come naturally to ZFS[*] -- well, in that case, ideally you want ZFS to have direct access to the disk devices= =2E With LSI, when they say 'JBOD' this direct access is generally what they mean -- although depending on the precise model you get, you may need to flash the device with different firmware to get the characteristics you want. Some other RAID controller manufacturers essentially give you a load of single-disk RAID-0 devices, so there's still a layer of RAID controller stuff between ZFS and the disk. That isn't the kiss of death to the idea of building a zpool from it, but it's less optimal. On the three aspecs you mention: performance depends very much on the precise type of disk hardware you specify, how you configure the zpool (for instance, will you be using ZIL or ARC devices?) and on having enough RAM in the system to provide an effective buffer-cache for all those ZFS filesystems. usability. I'd say ZFS is pretty usable. Once it's set up, you don't really need to interact with things at the level of the HBA. It just works. problems: this depends very much on the details of what you're trying to do. But IMHO you're on the right track with what you've described so far. Cheers, Matthew [*] Although poudriere does now work on UFS as well and has done for a year or so. --rp1u3UDDiuFjVOxa8Nlv0Ujjwss4mwktP Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQJ8BAEBCgBmBQJUa4IKXxSAAAAAAC4AKGlzc3Vlci1mcHJAbm90YXRpb25zLm9w ZW5wZ3AuZmlmdGhob3JzZW1hbi5uZXQxOUYxNTRFQ0JGMTEyRTUwNTQ0RTNGMzAw MDUxM0YxMEUwQTlFNEU3AAoJEABRPxDgqeTnsZ0QAKGStwjV+OIIkcnhbqAJJxIo iRPI/S80Xk65tnFnXIMz4+l3kJyhuyJNgVC9Z3DdnLTEPZBKY8CRzwpfxrreJXWg KkAn3k4UaUSCsyPiXX3pcCaXmpbmyVbja4yDCtH0JVMO6WboQaQAoVKJFnzlGnPd SFsqqmyxc8ILtT3uixjIoaRY0pjG9MUsS2YvjsrQ+CxNffvpoKiMVq8QqVFeAww9 4rKmCn+d6rgGuF6jCt+UEY9shKYXBVwRmnKwEzRCj4WwCBtd/rwBmoMuTbzOvoGc OOEWP++qyQIsuMvLItnqLPz2yuWZB+vME/L9EGULGjkTUOim21o9Y69s/cZPnELT npX4Y6SQFfdDX/v+bS7GS47yir5dDn8a8tLTsL/HvmkBmPZ98QokehCik0YXQ0WS swW2tB8shPHPKCYziEn0TA8nHJkBftEv2vEQh6VdcII7SeWgoHbr0p1DhRJlKL0T k2Ynkdu8zgugMoeQ+knwd4tnGiKLdhLp/PEGvR7O+2iwaBsCEj+VhSEciOUXYJqV aO2+2c+mGGGOgeSKltvP2H4CgSUqWUWk+tAHLQ5NE98viNs8UQAAWjiFpeDmB0NA ARiprAUC++t2GbjVt+q5cMLzPcK75lGauvAKr4++L2bECVusppeRA2ySRxZV4xd8 NCykZHBxnR9f9iN14UjH =cgfF -----END PGP SIGNATURE----- --rp1u3UDDiuFjVOxa8Nlv0Ujjwss4mwktP--
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?546B820A.7040806>