Re: Discard support (was Re: [PATCH] swap: send callback when swap slot is freed)

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 08/13/2009 08:43 PM, Matthew Wilcox wrote:


I am planning a complete overhaul of the discard work.  Users can send
down discard requests as frequently as they like.  The block layer will
cache them, and invalidate them if writes come through.  Periodically,
the block layer will send down a TRIM or an UNMAP (depending on the
underlying device) and get rid of the blocks that have remained unwanted
in the interim.


This batching of discard requests is still sub-optimal for compcache. The optimal solution in this case is to get callback *as soon as* a swap slot becomes free and this is what this patch does.

I see that it will be difficult to accept this patch since compcache seems to be the only user for now. However, this little addition makes a *big* difference for the project. Currently, much of memory is wasted to store all the stale data.

I will be posting compcache patches for review in next merge window. So, maybe this patch can be included now as the first step? The revised patch is ready which addresses issues raised during the first review -- will post it soon.

Thanks,
Nitin
--
To unsubscribe from this list: send the line "unsubscribe linux-ide" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[Index of Archives]     [Linux Filesystems]     [Linux SCSI]     [Linux RAID]     [Git]     [Kernel Newbies]     [Linux Newbie]     [Security]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Samba]     [Device Mapper]

  Powered by Linux