accumulo-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Josh Elser <josh.el...@gmail.com>
Subject Re: [DISCUSS] Question about 1.7 bugfix releases
Date Tue, 06 Jun 2017 18:20:27 GMT
On 6/6/17 2:13 PM, Sean Busbey wrote:
> On Tue, Jun 6, 2017 at 12:07 PM, Josh Elser <josh.elser@gmail.com> wrote:
>> On 6/6/17 12:39 PM, Sean Busbey wrote:
>>>
>>> For example, has anyone done perf comparisons between 1.7 and 1.8.z?
>>>
>>> When it came time for me to start telling folks that it was "safe" to
>>> upgrade to 1.7.z I ran into something like a 40-60% perf degradation
>>> on writes compared to 1.6 across the board. A little bit of this was
>>> already fixed in 1.8 at the time, but a substantial amount required a
>>> non-trivial refactoring because just no one had looked[1]. Even after
>>> all of that, I still had to caveat things because I still saw a
>>> ~15-30% perf drop on random writes in the presence of lots of columns.
>>
>>
>> At a risk of de-railing otherwise good discussion on releases: do you recall
>> if you had accounted for the following, Sean? (notably, the last code
>> snippet)
>>
>> https://accumulo.apache.org/blog/2016/11/02/durability-performance.html
> 
> I know that "set durability to flush and not sync" was one of the
> parameters for the comparison, but I don't remember what was done
> specifically during the testing back in September, tbh.
> 
> I can probably dig it out if you'd like; I think we were pretty good
> at keeping notes. Probably something for a different thread?
> 

Agreed. Just wanted to ask before I forgot again. Saw some relevance in 
the worry of perf regressions 1.7->1.8 based on the existence of those 
you saw 1.6->1.7, but def don't want to derail further here.

If you have the time and the notes, would be happy to review.

Mime
View raw message