FLUSH command to ATA disk;

NTDEV
1

Is there anything special thing that needs to be done by an ata controller/disk to receive FLUSH commands? My ata drive is not receiving FLUSH command from the system during normal run time. Then only FLUSH it receives is just before the shutdown (I think class driver generates this). Also when I send a FLUSH command explicitly from an upper disk filter driver it reaches my disk correctly. Any suggestions why my disk is not receiving FLUSHes from the system. In identify data writeCache supported and write cache Enabled flags are set and the drive is fixed, non-removable. Thanks.

2

why would you expect flush operations other than as observed?

On Thursday, November 19, 2009, wrote:
> Is there anything special thing that needs to be done by an ata controller/disk to receive FLUSH commands? My ata drive is not receiving FLUSH command from the system during normal run time. Then only FLUSH it receives is just before the shutdown (I think class driver generates this). Also when I send a FLUSH command explicitly from an upper disk filter driver it reaches my disk correctly. Any suggestions why my disk is not receiving FLUSHes from the system. ?In identify data writeCache supported and write cache Enabled flags are set and the drive is fixed, non-removable. Thanks.
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Mark Roddy

3

I format my drive and then copy large number of files to it. Shouldn’t system be sending flushes after these files are copied to my drive to make sure they are persistent on the media.

If I do the same on some other drive (not mine), I see flushes being sent to it.

So I need to know what is that missing in my drive (or driver).

Just to make sure that my miniport driver is working as expected I send some explicit flushes from a upper disk class filter driver and I observed that flush does reach my hardware as expected.

Thanks.