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

Badari Pulavarty
2003-03-24T22:57:32Z

On Monday 24 March 2003 04:10 pm, Andrew Morton wrote:
> Badari Pulavarty <pbadari@us.ibm.com> wrote:
> > Here is the list of slab caches which consumed more than 1 MB
> > in the process of inserting 4000 disks.
>
> Thanks for doing this.
>
> > #insmod scsi_debug.ko add_host=4 num_devs=1000
> >
> > deadline_drq before:1280 after:1025420 diff:1024140 size:64
> > incr:65544960 blkdev_requests before:1280 after:1025400 diff:1024120
> > size:156 incr:159762720
> >
> > * deadline_drq, blkdev_requests consumed almost 80 MB. We need to fix
> > this.
>
> Yes, we do. But.
>
> > inode_cache before:700 after:140770 diff:140070 size:364
> > incr:50985480 dentry_cache before:4977 after:145061 diff:140084
> > size:172 incr:24094448
> >
> > * inode cache increased by 50 MB, dentry cache 24 MB.
> > It looks like we cached 140,000 inodes. I wonder why ?
>
> # find /sys/block/hda | wc -l
> 43
>
> Oh shit, we're toast.
>
> How many partitions did these "disks" have?

These are all scsi_debug disks. No partitions.
Yeah !! I know what you mean, with partitions we
are going to get 5 more inodes per partition..

[root@elm3b78 sdaaa]# find /sysfs/block/sdaa
/sysfs/block/sdaa
/sysfs/block/sdaa/iosched
/sysfs/block/sdaa/iosched/fifo_batch
/sysfs/block/sdaa/iosched/front_merges
/sysfs/block/sdaa/iosched/writes_starved
/sysfs/block/sdaa/iosched/write_expire
/sysfs/block/sdaa/iosched/read_expire
/sysfs/block/sdaa/device
/sysfs/block/sdaa/stat
/sysfs/block/sdaa/size
/sysfs/block/sdaa/range
/sysfs/block/sdaa/dev

Thanks,
Badari