Re: [PERFORM] BBU still needed with SSD?

On 18/07/2011 9:43 AM, Andy wrote: Hi, Is BBU still needed with SSD? You *need* an SSD with a supercapacitor or on-board battery backup for its cache. Otherwise you *will* lose data. Consumer SSDs are like a hard disk attached to a RAID controller with write-back caching enabled and no BBU.

[PERFORM] BBU still needed with SSD?

Hi, Is BBU still needed with SSD? SSD has its own cache. And in certain models such as Intel 320 that cache is backed by capacitors. So in a sense that cache acts as a BBU that's backed by capacitors instead of batteries. In this case is BBU still needed? If I put 2 SSD in software RAID 1, w

Re: [PERFORM] UPDATEDs slowing SELECTs in a fully cached database

On 07/16/2011 06:33 PM, Jeff Janes wrote: 2.6 ms for an fsync seems awfully quick. I wonder if EBS uses nonvolatile/battery-backed write cache, or if it just lies about fsync actually hitting disk. They have the right type of cache in there to make fsync quick, when you happen to be the l