Re: [lc-devel] Announce: ccache release 0.1

[ace <ace...@at...>]

Hi.
Great to hear that! I tested it on kernel 2.6.24 and it seems to work.
But can you recommend any benchmark to test if using compcache actually
is any faster than normal swap? I am curious because I have an old
1.4Ghz CPU and a new harddisk (hdparm shows 166MB/s from cache, 66MB/s
from disk). The disk may actually be faster than all that compressing...
But probably random writes/reads from swap may kill that theoretical
linear read speed and the compressed memory wins. I'll try to come up
with something.
Thanks

Peter

Nitin Gupta wrote:
> Hi All,
> 
> I am excited to announce first release of ccache - Compressed RAM
> based swap device for Linux (2.6.x kernel).
>   - Project home: http://code.google.com/p/ccache/
>   - ccache-0.1: http://ccache.googlecode.com/files/ccache-0.1.tar.bz2
> 
> This is RAM based block device which acts as swap disk. Pages swapped
> to this device are compressed and stored in memory itself. This is
> especially useful for swapless embedded devices. Also, flash storage
> typically used in embedded devices suffer from wear-leveling issues -
> so, its very useful if we can avoid using them as swap device.
> And yes, its useful for desktops too :)
> 
> It does not require any kernel patching. All components are separate
> kernel modules:
> - Memory allocator (tlsf.ko)
> - Compressor (lzo1x_compress.ko)
> - Decompressor (lzo1x_decompress.ko)
> - Main ccache module (ccache.ko)
> (LZO de/compressor is already in mainline but I have included it here
> since distros don't ship it by default).
> README (or project home) explains compilation and usage in detail.
> 
> Some performance numbers for allocator and de/compressor can be found
> on project home. Currently it is tested on Linux kernel 2.6.23.x and
> 2.6.25-rc2 (x86 only). Please mail me/mailing-list any
> issues/suggestions you have.
> 
> Code reviews will be really helpful! :)
> 
> Thanks,
> - Nitin