Re: Badblocks and no free pages...

Chel van Gennip (
Sun, 4 May 1997 16:17:38 +0100 (WETDST)

Sun, 4 May 1997 Doug Ledford wrote:>
>> Can I report the following as bugs:
>> - The fact that badblocks doesn't help prevent accidents is a bit unfortunate.
>> - The fact that it generates "Couldn't get a free page" seems bad.
>> In particular, why should this happen during writing? What needs to
>> do an atomic page allocation?
>It's all because we are filling up all available RAM with write behind
>buffers. Whenever it can't get a free page, it simply waits for some to
>become available. Not a bug really, just shows us that the program is
>writing as fast as it can.
>> - The unusable sluggishness of the machine is a bug.
>It was never intended to be something that you would run during normal
>usage, it's a shake down, tear the drives and controllers apart type test
>that should be run when you are aware of what these types of tests do to
>machine performance and are prepared to wait for it to finish before
>actually trying to do anything :)

I noticed something alike when doing "mke2fs" on a 9GB volume in 2.0.28.
Is there a way to limit write behind buffers so more memory is available
for other uses. Allocating more than eg. 2Mbyte per device won't speed things
up I think. Programs like "badblocks" or "mke2fs" will use all available
space for buffering.