All of lore.kernel.org
 help / color / mirror / Atom feed
* Will drive flush cache on cable disconnect?
@ 2011-01-05 16:06 torn5
  0 siblings, 0 replies; only message in thread
From: torn5 @ 2011-01-05 16:06 UTC (permalink / raw)
  To: linux-scsi@vger.kernel.org

Sorry I am slightly OT

If I disconnect the SATA / SAS cable, or I suddenly power off the 
computer with the controller (this can be done if the drive is on a JBOD 
chassis with separate power) will the HDD/SSD go ahead flushing all 
write-cache content to the platters / flash media? (and so I would get a 
consistent filesystem/database on power on)

Or will it get mad when it returns completion for each write command and 
nobody is listening on the other end of the cable? (cable disconnected 
or controller powered off)

Now another question:
When the drive is doing cached writes (cache on), without NCQ 
(queue_depth at 1), is the "completion" returned immediately upon 
receiving the write command, or is it returned later when the data goes 
to the platters? If it's the latter, what is the difference with NCQ 
(queue_depth > 1) then?

Thank you

^ permalink raw reply	[flat|nested] only message in thread

only message in thread, other threads:[~2011-01-05 16:06 UTC | newest]

Thread overview: (only message) (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2011-01-05 16:06 Will drive flush cache on cable disconnect? torn5

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.