Re: [RFC] LZO de/compression support - take 3

["Bret Towe" <magnade@gmail.com>]

On 5/24/07, Nitin Gupta <nitingupta910@gmail.com> wrote:
> On 5/25/07, Bret Towe <magnade@gmail.com> wrote:
> > On 5/24/07, Nitin Gupta <nitingupta910@gmail.com> wrote:
> > > On 5/23/07, Bret Towe <magnade@gmail.com> wrote:
> > > > On 5/23/07, Nitin Gupta <nitingupta910@gmail.com> wrote:
> > >
> > > > > For now, tested on x86 only.
> > > >
> > > > If you have a program to test this I can run it on an amd64 and a g4 ppc
> > > >
> > >
> > > Attached is the kernel module (compress-test) to test this LZO code.
> > > Just compile this module against 2.6.22-rc2 with this LZO patch. Then
> > > testing can be done as:
> > > 1- Mount DebugFS somewhere e.g:
> > > mkdir /debug; mount -t debugfs debugfs /debug
> > > 2- Load the module and do:
> > > cat /path/to/some_file > /debug/compress_test/compress
> > > (/var/log/messages should show that compression was successful)
> > > 3- Then decompress this file as:
> > > cat /debug/compress_test/decompress > /tmp/t
> > > (/var/log/messages should show that decompression was successful)
> > > 4- For extra verification do:
> > > diff /tmp/t /path/to/some_file   -- O/P must be empty
> > >
> > >
> >
> > the test worked fine on amd64
> > from dmesg:
> > LZO compress successful: orig_size=17448, comp_size=8183
> > LZO decompress successful: decomp_size=17448
> >
> > and input and output files I gave it:
> > sha1sum test-input output
> > 2221c586e3eb869af7f4333d4f56b441b9aa8414  test-input
> > 2221c586e3eb869af7f4333d4f56b441b9aa8414  output
> >
>
> Good to know it worked correctly on 64-bit system too. I will also
> add exporting benchmarking figures soon.
>
> > (will be giving the ppc box the same file to test btw when I get to it)

[  237.556167] LZO compress successful: orig_size=17448, comp_size=8183
[  253.320760] LZO decompress successful: decomp_size=17448

2221c586e3eb869af7f4333d4f56b441b9aa8414  test-input
2e6c96b687274b629308b29835cebd3af989e0c7  output

ppc however seems bust
the computer is a g4 mini

> > and I don't know if it matters much but I tried feeding it a 260k file
> > and it didn't like it
> >
> > cat /usr/bin/yelp > /debug/compress_test/compress
> > cat: write error: No space left on device
> >
>
> Ah! I forgot to mention that max file size to feed is 256K (this was
> just for simplicity of compress-test module implementation).

figured it might be something like that

> Thanks for your testing.

no problem

> - Nitin
>