On Thu, 25 Jan 2024 00:43:51 +0900, Akira Yokosawa wrote:
> On Wed, 24 Jan 2024 08:25:57 -0700, Jonathan Corbet wrote:
>> Akira Yokosawa <akiyks@xxxxxxxxx> writes:
[...]
>>> VM spec used: memory: 8GB, threads: 4, ubuntu jammy
>>>
>>> data in each cell: elapsed time, max resident memory
>>>
>>> v2.4.5 v4.3.2 v7.2.6
>>> ============================= ============ ============ ============
>>> clean build at v6.7 10m08s 3.3GB 10m31s 1.1GB 10m14s 1.2GB
>>> incremental build at v6.8-rc1 11m22s 3.3GB 18m55s 1.2GB 19m50s 1.4GB
>>> clean build at v6.8-rc1 10m45s 3.2GB 10m32s 1.2GB 10m13s 1.3GB
>>>
>>> empty make at v6.8-rc1 3.3s 6.6s 7.0s
>>> ============================= ============ ============ ============
>>
>> So that is quite different from my experience. For me, full builds got
>> way slower starting with 3.x and haven't improved much since, though
>> I've not played much with 7.x yet.
>
> One of the reasons I can think of why 2.4.5 is not faster is
> the "make -j2" I need to use. 2.4.x is way more eager to use
> more parallel slots than >=3.1 in later stages of its processing.
> I think you have a memory rich system that allows a lot of parallel
> slots. On a machine with 16GB memory, I can say -j4 (or -j5 if
> I am lucky).
>
So, I managed to run v2.4.5 with 4 threads.
Also, I ran incremental builds of small diffs at the docs-6.8-fixes
tag relative to v6.8-rc1.
Here is the updated table.
-----------------------------------------
VM spec used: memory: 10GB, threads: 4, ubuntu jammy
data in each cell: elapsed time, max resident memory
v2.4.5 v4.3.2 v7.2.6
============================ =========== ============ ============
full build at v6.7 6m14s 2.3GB 10m31s 1.1GB 10m14s 1.2GB
incr build at v6.8-rc1 7m26s 2.5GB 18m55s 1.2GB 19m50s 1.4GB
full build at v6.8-rc1 6m45s 2.4GB 10m32s 1.2GB 10m13s 1.3GB
incr build at docs-6.8-fixes 4m58s 2.2GB 6m50s 1.2GB 6m45s 1.3GB
empty make at v6.8-rc1 3.3s 6.6s 7.0s
============================ =========== ============ ============
This should be close to the reality.
HTH, Akira
