Re: [patch for playing] 2.5.65 patch to support > 256 disks

Badari Pulavarty
2003-03-27T00:29:34Z

On Tuesday 25 March 2003 04:35 am, Jens Axboe wrote:

> Only testing will tell, so yes you are very welcome to give it a shot.
> Let me release a known working version first :)

Jens,

I found whats using 32MB out of 8192-byte slab.

size-8192 before:10 after:4012 diff:4002 size:8192 incr:32784384

It is deadline_init():

dd->hash = kmalloc(sizeof(struct list_head)*DL_HASH_ENTRIES,GFP_KERNEL);

It is creating 8K hash table for each queue. Since we have 4000 queues,
it used 32MB. I wonder why the current code needs 1024 hash buckets,
when maximum requests are only 256. And also, since you are making
request allocation dynamic, can you change this too ? Any issues here ?

Thanks,
Badari