Improving ramdisk uncompression time...

Improving ramdisk uncompression time...

[Subodh Nijsure]

Hello,

My setup has rather large ramdisk 5MB as the ramdisk contains
firmware for other boards in the system. In total boot time of
about 60 seconds, close to 50% is spent in uncompressing the ramdisk.

Has anybody tried building ramdisk with bizp2, what other ideas
one might consider to "speed up" the boot time particularly uncompressing
the ramdisk...

/Subodh Nijsure

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Re: Improving ramdisk uncompression time...

[Nguyen Trung Thanh]

Hi,

We can make a specific ramdisk by splitting it into
64KB parts, and let it there...
Everytime, we need to read some thing from ramdisk,
we read from the buffer or decompress a part from
that ramdisk.
It'll save you much time while booting and more than 2MB RAM, as well.

Is it cool?
Jari

----- Original Message -----
From: "Subodh Nijsure" <SNijsure@SkyStream.com>
>
> Hello,
>
> My setup has rather large ramdisk 5MB as the ramdisk contains
> firmware for other boards in the system. In total boot time of
> about 60 seconds, close to 50% is spent in uncompressing the ramdisk.
>
> Has anybody tried building ramdisk with bizp2, what other ideas
> one might consider to "speed up" the boot time particularly uncompressing
> the ramdisk...
>
> /Subodh Nijsure


** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/

Re: Improving ramdisk uncompression time...

[Kenneth Johansson]

Subodh Nijsure wrote:
>
> Hello,
>
> My setup has rather large ramdisk 5MB as the ramdisk contains
> firmware for other boards in the system. In total boot time of
> about 60 seconds, close to 50% is spent in uncompressing the ramdisk.

I have a 10MB ramdisk when compresses is a little over 2MB. On a 405 in
200MHz this takes 1 second to uncompress.

Are you sure you have cache working.

You could try to use cramfs. Then the the data don't have to be uncompressed.
I think I have not used it myself.

--
Kenneth Johansson
Ericsson Business Innovation AB   Tel: +46 8 404 71 83
Viderögatan 3                     Fax: +46 8 404 72 72
164 80 Stockholm                  kenneth.johansson@inn.ericsson.se

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