On 1/24/14, 10:22 AM, Roberto Spadim wrote: > i don't know there's space to improvement here, i got 1% of speed up > doing a mix of disk speed (7.2k rpm 5k rpm and 15k rpm and a ssd) and > changing the read balance algorithm If your RAID1 array contains both spinning disks and SSDs, you can (and should) simply set the spinning disks as "write-mostly": http://tansi.info/hybrid/ This causes all reads to come from the SSD if possible. After doing this, all reads should be at the SSD speed, although all writes will still be at spinning disk speeds. We have been doing this on all our database servers for years with zero problems (although we finally now trust SSDs enough to switch all array members to SSDs, so we're phasing it out). If your workload consists of lots of scattered reads, you'll get far more than a 1% read performance increase from this, with no tweaking of read balancing algorithm necessary. -- Robert L Mathews, Tiger Technologies, http://www.tigertech.net/ -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
