Hi,

On Mon, Jun 03, 2019 at 06:06:02PM +0900, flamese...@yahoo.co.jp wrote:
> I recently found that compression performance drops down after I update to 
> v1.9
> 
> I dug a little bit and found that there are many forward calls with a length 
> of zero
> 
> Breakpoint 1, comp_http_forward_data (s=0x86a620, filter=0x873c70, 
> msg=0x86b960, len=0) at src/flt_http_comp.c:386
>
> which did not happen in version 1.8 

I could indeed reproduce it and it is a side effect of an optimization
that is not relevant anymore and which even caused some trouble recently. 
It also had the bad side effect of feeding the compressor with less data
per call resulting in a lower compression ratio. I've addressed it with
commit a689c3d8d ("MEDIUM: stream: make a full process_stream() loop when
completing I/O on exit") which also happens to fix the tricks for which
some loop detection code was added to process_stream().

For me it significantly improves the situation and in fact I'm seeing
that under certain circumstances I could even make the process crash
in the loop detection before this patch, which doesn't happen anymore.

I'd be interested in hearing about your comparison with 1.8. Also please
note that HTX mode is enabled by default in 2.0-dev while it didn't exist
in 1.8, so you may be interested in testing with and without (disable it
using "no option http-use-htx").

Regards,
Willy

Reply via email to