Re: [PATCH 1/2] zram: free meta out of init_lock

Sergey Senozhatsky
2015-01-28T04:50:33Z

On (01/28/15 13:07), Sergey Senozhatsky wrote:
> On (01/28/15 12:53), Sergey Senozhatsky wrote:
> > > So, I want to go with srcu. Do you agree? or another suggestion?
> >
> > yes, I think we need to take a second look on srcu approach.
> >
>
> ... or we can ask lockdep to stop false alarming us and leave it as is.
> I wouldn't say that ->init_lock is so hard to understand.
> just as an option.
>

so... returning back to barriers performance implications.

x86_64, lzo, 4 comp streams, 2G zram, ext4, mount -o rw,relatime,data=ordered

./iozone -t 3 -R -r 16K -s 60M -I +Z

test base srcu
" Initial write " 1299639.75 1277621.03
" Rewrite " 2139387.50 2004663.94
" Read " 6193415.00 5091000.00
" Re-read " 6199050.38 4814297.88
" Reverse Read " 4693868.88 4367201.75
" Stride read " 4470633.75 4247550.00
" Random read " 5115339.50 4517352.75
" Mixed workload " 4340747.06 3880517.31
" Random write " 1982369.75 1892456.25
" Pwrite " 1352550.22 1248667.78
" Pread " 2853150.06 2445154.41
" Fwrite " 2367397.81 2262384.56
" Fread " 8100746.50 7578071.75

not good.

-ss