[PATCH 0/3] zram: generic RAM based compressed R/W block devices
Nitin Gupta
ngupta at vflare.org
Fri May 28 16:08:53 UTC 2010
Hi All,
On 05/24/2010 07:48 PM, Nitin Gupta wrote:
> Creates RAM based block devices: /dev/zramX (X = 0, 1, ...).
> Pages written to these disks are compressed and stored in memory
> itself. These disks allow very fast I/O and compression provides
> good amounts of memory savings.
>
> This is enhancement over existing ramzswap driver which creates
> virtual block devices (/dev/ramzswapX) which could be used only
> as swap disks.
>
> Now, with the ability to handle any kind of I/O request, zram
> devices have lot more use cases:
> - /tmp storage
> - various caches under /var
> - swap disks
> - maybe even more! :)
>
> Performance numbers can be found at:
> http://code.google.com/p/compcache/wiki/zramperf
>
Any reviews/comments, please?
I also performed iozone tests to stress zram:
http://code.google.com/p/compcache/wiki/zramIOzone
Note that the effect of pagecache could not be completely
avoided, even when pagecache was dropped every 1 second.
So, this iozone test should not be considered for speed
measurements but as a stress test only. For speed tests,
you can refer 'dd' test results included in changelog (patch 1).
No errors were observed during either iozone or dd tests.
Thanks,
Nitin
More information about the devel
mailing list