Re: [LKP] [lkp] [xfs] 68a9f5e700: aim7.jobs-per-min -13.6% regression

From: Dave Chinner
Date: Wed Aug 10 2016 - 21:32:47 EST


On Thu, Aug 11, 2016 at 11:16:12AM +1000, Dave Chinner wrote:
> I need to see these events:
>
> xfs_file*
> xfs_iomap*
> xfs_get_block*
>
> For both kernels. An example trace from 4.8-rc1 running the command
> `xfs_io -f -c 'pwrite 0 512k -b 128k' /mnt/scratch/fooey doing an
> overwrite and extend of the existing file ends up looking like:
>
> $ sudo trace-cmd start -e xfs_iomap\* -e xfs_file\* -e xfs_get_blocks\*
> $ sudo cat /sys/kernel/tracing/trace_pipe
> <...>-2946 [001] .... 253971.750304: xfs_file_ioctl: dev 253:32 ino 0x84
> xfs_io-2946 [001] .... 253971.750938: xfs_file_buffered_write: dev 253:32 ino 0x84 size 0x40000 offset 0x0 count 0x20000
> xfs_io-2946 [001] .... 253971.750961: xfs_iomap_found: dev 253:32 ino 0x84 size 0x40000 offset 0x0 count 131072 type invalid startoff 0x0 startblock 24 blockcount 0x60
> xfs_io-2946 [001] .... 253971.751114: xfs_file_buffered_write: dev 253:32 ino 0x84 size 0x40000 offset 0x20000 count 0x20000
> xfs_io-2946 [001] .... 253971.751128: xfs_iomap_found: dev 253:32 ino 0x84 size 0x40000 offset 0x20000 count 131072 type invalid startoff 0x0 startblock 24 blockcount 0x60
> xfs_io-2946 [001] .... 253971.751234: xfs_file_buffered_write: dev 253:32 ino 0x84 size 0x40000 offset 0x40000 count 0x20000
> xfs_io-2946 [001] .... 253971.751236: xfs_iomap_found: dev 253:32 ino 0x84 size 0x40000 offset 0x40000 count 131072 type invalid startoff 0x0 startblock 24 blockcount 0x60
> xfs_io-2946 [001] .... 253971.751381: xfs_file_buffered_write: dev 253:32 ino 0x84 size 0x40000 offset 0x60000 count 0x20000
> xfs_io-2946 [001] .... 253971.751415: xfs_iomap_prealloc_size: dev 253:32 ino 0x84 prealloc blocks 128 shift 0 m_writeio_blocks 16
> xfs_io-2946 [001] .... 253971.751425: xfs_iomap_alloc: dev 253:32 ino 0x84 size 0x40000 offset 0x60000 count 131072 type invalid startoff 0x60 startblock -1 blockcount 0x90
>
> That's the output I need for the complete test - you'll need to use
> a better recording mechanism that this (e.g. trace-cmd record,
> trace-cmd report) because it will generate a lot of events. Compress
> the two report files (they'll be large) and send them to me offlist.

Can you also send me the output of xfs_info on the filesystem you
are testing?

Cheers,

Dave.
--
Dave Chinner
david@xxxxxxxxxxxxx