4 ms·
A Raid 5 could work, since you are not writing the same data. You would need a hardware coprocessor to handle generating the checksums at 4GB/s though.
by zanny 11y ago
A Raid 5 could work, since you are not writing the same data. You would need a hardware coprocessor to handle generating the checksums at 4GB/s though.
- pixl97 11y ago>You would need a hardware coprocessor to handle generating the checksums at 4GB/s though. A first gen i5 2.4GHz can generate XOR for RAID5 at 4GB/s. Newer generations at faster core speeds should be able to beat that significantly. ... I went and tested this on a Intel(R) Xeon(R) CPU E3-1220 v3 @ 3.10GHz [1053854.445872] avx : 17860.000 MB/sec [1053854.475878] raid6: sse2x1 gen() 6554 MB/s [1053854.492857] raid6: sse2x2 gen() 9070 MB/s [1053854.509853] raid6: sse2x4 gen() 11273 MB/s [1053854.526848] raid6: avx2x1 gen() 21554 MB/s [1053854.543844] raid6: avx2x2 gen() 25152 MB/s [1053854.560838] raid6: avx2x4 gen() 29167 MB/s [1053854.560839] raid6: using algorithm avx2x4 gen() (29167 MB/s) [1053854.560840] raid6: using avx2x2 recovery algorithm
- ryao 11y agoRAID 5 is terrible with 4K random IO. I know guys who measured >1 million IOPS with MD RAID 0 and then switched to MD RAID 5 only to have performance drop from read-modify-write overhead. They could not believe that RAID 5 was the cause.