[lld] r232460 - [ELF] Use parallel_for_each for writing.

[Shankar Easwaran]

Unfortunately, I only have a very lowend windows setup :(

On 3/18/2015 11:32 AM, Rafael Espíndola wrote:
> As with anything threading related, it might also be worth
> benchmarking it on Windows.
>
> On 18 March 2015 at 12:31, Shankar Easwaran <shankare at codeaurora.org> wrote:
>> It looks like these are the right numbers and Strange, I dont see a huge
>> advantage of the patch trying to parallelize writing output sections in
>> parallel.
>>
>>
>> On 3/18/2015 11:23 AM, Rafael Espíndola wrote:
>>> On 18 March 2015 at 12:14, Shankar Easwaran <shankare at codeaurora.org>
>>> wrote:
>>>> Does this repeat with the same numbers across similar tries ?
>>> The "-r 20" tells perf to do 20 runs. Repeating the entire thing for
>>> sanity check I got
>>>
>>>
>>> master:
>>>          1850.315854      task-clock (msec)         #    0.999 CPUs
>>> utilized            ( +-  0.20% )
>>>                1,246      context-switches          #    0.673 K/sec
>>>                    0      cpu-migrations            #    0.000 K/sec
>>>                  ( +-100.00% )
>>>              191,223      page-faults               #    0.103 M/sec
>>>                  ( +-  0.00% )
>>>        5,570,279,746      cycles                    #    3.010 GHz
>>>                  ( +-  0.08% )
>>>        3,076,652,220      stalled-cycles-frontend   #   55.23% frontend
>>> cycles idle     ( +-  0.15% )
>>>      <not supported>      stalled-cycles-backend
>>>        6,061,467,442      instructions              #    1.09  insns per
>>> cycle
>>>                                                     #    0.51  stalled
>>> cycles per insn  ( +-  0.00% )
>>>        1,262,014,047      branches                  #  682.053 M/sec
>>>                  ( +-  0.00% )
>>>           26,526,169      branch-misses             #    2.10% of all
>>> branches          ( +-  0.00% )
>>>
>>>          1.852094924 seconds time elapsed
>>>             ( +-  0.20% )
>>>
>>> master minus your patch:
>>>
>>>          1837.986418      task-clock (msec)         #    0.999 CPUs
>>> utilized            ( +-  0.01% )
>>>                1,170      context-switches          #    0.637 K/sec
>>>                    0      cpu-migrations            #    0.000 K/sec
>>>              191,225      page-faults               #    0.104 M/sec
>>>                  ( +-  0.00% )
>>>        5,517,484,340      cycles                    #    3.002 GHz
>>>                  ( +-  0.01% )
>>>        3,036,583,530      stalled-cycles-frontend   #   55.04% frontend
>>> cycles idle     ( +-  0.02% )
>>>      <not supported>      stalled-cycles-backend
>>>        6,004,436,870      instructions              #    1.09  insns per
>>> cycle
>>>                                                     #    0.51  stalled
>>> cycles per insn  ( +-  0.00% )
>>>        1,250,685,716      branches                  #  680.465 M/sec
>>>                  ( +-  0.00% )
>>>           26,539,486      branch-misses             #    2.12% of all
>>> branches          ( +-  0.00% )
>>>
>>>          1.839759787 seconds time elapsed
>>>             ( +-  0.01% )
>>>
>>>
>>> Cheers,
>>> Rafael
>>>
>>
>> --
>> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by
>> the Linux Foundation
>>


-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by the Linux Foundation