How slow and how reliable is software raid 6 on CentOS 5. The system I'm going to use is A socket 939 dual core Athlon, 4 gigs of ram and a 3ware 7506-8 controller. Its mostly going to be used for storage (Movies, MP3s etc.). Thanks.
Juan C. Valido wrote:
How slow and how reliable is software raid 6 on CentOS 5. The system I'm going to use is A socket 939 dual core Athlon, 4 gigs of ram and a 3ware 7506-8 controller. Its mostly going to be used for storage (Movies, MP3s etc.). Thanks.
The 7506 does not have any cache. Its ASIC chips have very limited storage. You are far better off running in raid10 with the 75xx and 85xx series. Those cards are especially slow when you get a degraded array in raid5 or raid6 (not sure if the 75xx or the 85xx support raid6) mode due to the lack of cache.
So you get the benefit of multiple spindles but I personally will not use anything but raid1 or raid10 with a 75xx or 85xx series 3ware board.
Feizhou wrote:
Juan C. Valido wrote:
How slow and how reliable is software raid 6 on CentOS 5. The system I'm going to use is A socket 939 dual core Athlon, 4 gigs of ram and a 3ware 7506-8 controller. Its mostly going to be used for storage (Movies, MP3s etc.). Thanks.
Argh...just read the SOFTWARE RAID 6. Man, does the 3ware turn me into hardware mode...
I do not know...I personally have stayed away from linux software raid for raid5/6. You might actually find raid10 hardware mode to be faster than software raid 5/6 but at the cost of less storage and but better reliability in power loss cases.
The 7506 does not have any cache. Its ASIC chips have very limited storage. You are far better off running in raid10 with the 75xx and 85xx series. Those cards are especially slow when you get a degraded array in raid5 or raid6 (not sure if the 75xx or the 85xx support raid6) mode due to the lack of cache.
So you get the benefit of multiple spindles but I personally will not use anything but raid1 or raid10 with a 75xx or 85xx series 3ware board. _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
-----Original Message----- From: centos-bounces@centos.org [mailto:centos-bounces@centos.org] On Behalf Of Feizhou Sent: Sunday, September 16, 2007 9:35 AM To: CentOS mailing list Subject: Re: [CentOS] Software Raid 6
Feizhou wrote:
Juan C. Valido wrote:
How slow and how reliable is software raid 6 on CentOS 5. The system I'm going to use is A socket 939 dual core Athlon, 4 gigs of ram and a 3ware 7506-8 controller. Its mostly going to be used for storage (Movies, MP3s etc.). Thanks.
Argh...just read the SOFTWARE RAID 6. Man, does the 3ware turn me into hardware mode...
I do not know...I personally have stayed away from linux software raid for raid5/6. You might actually find raid10 hardware mode to be faster than software raid 5/6 but at the cost of less storage and but better reliability in power loss cases.
The 7506 does not have any cache. Its ASIC chips have very limited storage. You are far better off running in raid10 with the 75xx and 85xx series. Those cards are especially slow when you get a degraded array in raid5 or raid6 (not sure if the 75xx or the 85xx support raid6) mode due to the lack of cache.
So you get the benefit of multiple spindles but I personally will not use anything but raid1 or raid10 with a 75xx or 85xx series 3ware board. _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
_______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos Thanks, that's what I'm running now, I guess I'll add more space elsewhere.
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Feizhou -
Juan C. Valido