On Wed, 2020-11-11 at 11:34 +0100, Thomas Bendler wrote:> Am Mi., 11. Nov. 2020 um 07:28 Uhr schrieb hw <hw at gc-24.de>: > > > [...] > > With this experience, these controllers are now deprecated. RAID > > controllers > > that can't rebuild an array after a disk has failed and has been replaced > > are virtually useless. > > [...] > > HW RAID is often delivered with quite limited functionality. Because of > this I switched in most cases to software RAID meanwhile and configured the > HW RAID as JBOD. The funny thing is, when you use the discs previously used > in the HW RAID in such a scenario, the software RAID detects them as RAID > disks. It looks like a significant amount of HW RAID controllers use the > Linux software RAID code in their firmware. >I have yet to see software RAID that doesn't kill the performance. And where do you get cost-efficient cards that can do JBOD? I don't have any. It turned out that the controller does not rebuild the array even with a disk that is the same model and capacity as the others. What has HP been thinking?
On Nov 11, 2020, at 2:01 PM, hw <hw at gc-24.de> wrote:> > I have yet to see software RAID that doesn't kill the performance.When was the last time you tried it? Why would you expect that a modern 8-core Intel CPU would impede I/O in any measureable way as compared to the outdated single-core 32-bit RISC CPU typically found on hardware RAID cards? These are the same CPUs, mind, that regularly crunch through TLS 1.3 on line-rate fiber Ethernet links, a much tougher task than mediating spinning disk I/O.> And where > do you get cost-efficient cards that can do JBOD?$69, 8 SATA/SAS ports: https://www.newegg.com/p/0ZK-08UH-0GWZ1 Search for ?LSI JBOD? for tons more options. You may have to fiddle with the firmware to get it to stop trying to do clever RAID stuff, which lets you do smart RAID stuff like ZFS instead.> What has HP been thinking?That the hardware vs software RAID argument is over in 2020.
On Wed, Nov 11, 2020 at 3:38 PM Warren Young <warren at etr-usa.com> wrote:> On Nov 11, 2020, at 2:01 PM, hw <hw at gc-24.de> wrote: > > > > I have yet to see software RAID that doesn't kill the performance. > > When was the last time you tried it? > > Why would you expect that a modern 8-core Intel CPU would impede I/O in > any measureable way as compared to the outdated single-core 32-bit RISC CPU > typically found on hardware RAID cards? These are the same CPUs, mind, > that regularly crunch through TLS 1.3 on line-rate fiber Ethernet links, a > much tougher task than mediating spinning disk I/O.the only 'advantage' hardware raid has is write-back caching. with ZFS you can get much the same performance boost out of a small fast SSD used as a ZIL / SLOG. -- -john r pierce recycling used bits in santa cruz
> On Nov 11, 2020, at 5:38 PM, Warren Young <warren at etr-usa.com> wrote: > > On Nov 11, 2020, at 2:01 PM, hw <hw at gc-24.de> wrote: >> >> I have yet to see software RAID that doesn't kill the performance. > > When was the last time you tried it? > > Why would you expect that a modern 8-core Intel CPU would impede I/O in any measureable way as compared to the outdated single-core 32-bit RISC CPU typically found on hardware RAID cards? These are the same CPUs, mind, that regularly crunch through TLS 1.3 on line-rate fiber Ethernet links, a much tougher task than mediating spinning disk I/O. > >> And where >> do you get cost-efficient cards that can do JBOD? > > $69, 8 SATA/SAS ports: https://www.newegg.com/p/0ZK-08UH-0GWZ1 > > Search for ?LSI JBOD? for tons more options. You may have to fiddle with the firmware to get it to stop trying to do clever RAID stuff, which lets you do smart RAID stuff like ZFS instead.I?m sure you can reflash LSI card to make it SATA or SAS HBA, or MegaRAD hardware RAID adapter. Is far as I recollect it is the same electronics board. I reflashed a couple of HBAs to make them MegaRAID boards. One thing though bothers me about LSI, now after last it was bought by Intel its future faith worries me. Intel pushed 3ware which it acquired in the same package with LSI already into oblivion? Valeri>> What has HP been thinking? > > That the hardware vs software RAID argument is over in 2020. > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > https://lists.centos.org/mailman/listinfo/centos
> On Nov 11, 2020, at 5:38 PM, Warren Young <warren at etr-usa.com> wrote: > > On Nov 11, 2020, at 2:01 PM, hw <hw at gc-24.de> wrote: >> >> I have yet to see software RAID that doesn't kill the performance. > > When was the last time you tried it? > > Why would you expect that a modern 8-core Intel CPU would impede I/O in any measureable way as compared to the outdated single-core 32-bit RISC CPU typically found on hardware RAID cards? These are the same CPUs, mind, that regularly crunch through TLS 1.3 on line-rate fiber Ethernet links, a much tougher task than mediating spinning disk I/O. > >> And where >> do you get cost-efficient cards that can do JBOD? > > $69, 8 SATA/SAS ports: https://www.newegg.com/p/0ZK-08UH-0GWZ1 > > Search for ?LSI JBOD? for tons more options. You may have to fiddle with the firmware to get it to stop trying to do clever RAID stuff, which lets you do smart RAID stuff like ZFS instead. > >> What has HP been thinking? > > That the hardware vs software RAID argument is over in 2020.I?d rather have distributed redundant storage on multiple machines? but I still have [mostly] hardware RAIDs ;-) Valeri> _______________________________________________ > CentOS mailing list > CentOS at centos.org > https://lists.centos.org/mailman/listinfo/centos
On Wed, 2020-11-11 at 16:38 -0700, Warren Young wrote:> On Nov 11, 2020, at 2:01 PM, hw <hw at gc-24.de> wrote: > > I have yet to see software RAID that doesn't kill the performance. > > When was the last time you tried it?I'm currently using it, and the performance sucks. Perhaps it's not the software itself or the CPU but the on-board controllers or other components being incable handling multiple disks in a software raid. That's something I can't verify.> Why would you expect that a modern 8-core Intel CPU would impede I/O in any measureable way as compared to the outdated single-core 32-bit RISC CPU typically found on hardware RAID cards? These are the same CPUs, mind, that regularly crunch through TLS 1.3 on line-rate fiber Ethernet links, a much tougher task than mediating spinning disk I/O.It doesn't matter what I expect.> > And where > > do you get cost-efficient cards that can do JBOD? > > $69, 8 SATA/SAS ports: https://www.newegg.com/p/0ZK-08UH-0GWZ1That says it's for HP. So will you still get firmware updates once the warranty is expired? Does it exclusively work with HP hardware? And are these good?> Search for ?LSI JBOD? for tons more options. You may have to fiddle with the firmware to get it to stop trying to do clever RAID stuff, which lets you do smart RAID stuff like ZFS instead. > > > What has HP been thinking? > > That the hardware vs software RAID argument is over in 2020. >Do you have a reference for that, like a final statement from HP? Did they stop developing RAID controllers, or do they ship their servers now without them and tell customers to use btrfs or mdraid?