[Mesa-dev] [PATCH V2] util/disk_cache: compress individual cache entries

[Emil Velikov]

On 2 March 2017 at 21:52, Timothy Arceri <tarceri at itsqueeze.com> wrote:
>
> On 03/03/17 01:49, Emil Velikov wrote:
>>
>> Hi Tim,
>>
>> On 2 March 2017 at 01:36, Timothy Arceri <tarceri at itsqueeze.com> wrote:
>>>
>>> This reduces the cache size for Deus Ex from ~160M to ~30M for
>>> radeonsi.
>>>
>>> I'm also seeing the following improvements in minimum fps in the
>>> Shadow of Mordor benchmark:
>>>
>>> no-cache:                    ~10fps
>>> with-cache-no-compression:   ~15fps
>>> with-cache-and-compression:  ~20fps
>>>
>>> Note the with cache results are from the second run after closing
>>> and opening the game to avoid the in-memory cache.
>>>
>>> Since we only really care about decompression I went with
>>> Z_BEST_COMPRESSION as suggested on irc by Steinar H. Gunderson
>>> who has benchmarked decompression speeds.
>>>
>> Attempting to side-step the "which compression is best" topic, I'll
>> just mention:
>> zlib has been around for a long time than many others so,
>> a) chances are smaller that vendors that ship their own, but even if they
>> do
>> b) the API should be stable across the system and bundled one.
>>
>> If not we can reconsider if things get hairy ;-)
>>
>> A couple of small suggestions below.
>>
>>
>>> +ZLIB_REQUIRED=1.2.8
>>>
>> Any particular reason behind this version - afaict it's released in
>> 2013 and I'm wondering if some distros may be slow/missing it.
>>
>
> It's what's shipped with Fedora and therefore what I tested with. If distros
> are lagging behind I don't think this is a problem we need to be concerned
> with, it may prompt them to upgrade which I don't think is a bad thing.
>
I was thinking about Debian and friends, which tend to be slower than others.
>From what I can tell they rarely consider external factors as a reason
to update.

That aside, they have 1.2.7 for "oldstable" and 1.2.8 for everything
else so everything's fine.

-Emil