ILP32 for ARM64 - testing with lmbench

Zhangjian (Bamvor)
2016-12-05T10:16:09Z

Hi, Catalin, Guys

Do you have suggestion of next move of upstreaming ILP32?
There are already the test results of lmbench and specint. Do you they are ok or need more data to prove no regression?
I have also noticed that there are ILP32 failures in glibc testsuite. Is it the only blocker for merge ILP32(in technology part)?

We appreciate any feedback/suggestion and hope could collaborate to improve the upstream progress.

(cc libc-alpha to get more input).

Thanks

Bamvor

On 2016/11/17 15:48, Zhangjian (Bamvor) wrote:
> Hi, Maxim
>
> On 2016/11/17 13:02, Maxim Kuvyrkov wrote:
>> Hi Bamvor,
>>
>> I'm surprised that you see this much difference from ILP32 patches on SPEC CPU2006int at all. The SPEC CPU2006 benchmarks spend almost no time in the kernel syscalls. I can imagine memory, TLB,
>> and cache handling in the kernel could affect CPU2006 benchmarks. Do ILP32 patches touch code in those areas?
>>
>> Other than that, it would be interesting to check what the variance is between the 3 iterations of benchmark runs. Could you check what relative standard deviation is between the 3 iterations --
>> (STDEV(RUN1, RUN2, RUN3) / RUNselected)?
>>
>> For reference, in my [non-ILP32] benchmarking I see 1.1% for 401.bzip2, 0.8% for 429.mcf, 0.2% for 456.hmmer, and 0.1% for 462.libquantum.
> Here is my result:
> ILP32_merged ILP32_unmerged
> 401.bzip2 0.31% 0.26%
> 429.mcf 1.61% 1.36%
> 456.hmmer 1.37% 1.57%
> 462.libquantum 0.29% 0.28%
>
> Regards
>
> Bamvor
>
>>
>> --
>> Maxim Kuvyrkov
>> www.linaro.org
>>
>>
>>
>>> On Nov 17, 2016, at 7:28 AM, Zhangjian (Bamvor) <bamvor.zhangjian@huawei.com> wrote:
>>>
>>> Hi, all
>>>
>>> I test specint of aarch64 LP64 when aarch32 el0 disable/enabled respectively
>>> and compare with ILP32 unmerged kernel(4.8-rc6) in our arm64 board. I found
>>> that difference(ILP32 disabled/ILP32 unmerged) is bigger when aarch32 el0 is
>>> enabled, compare with aarch32 el0 disabled kernel. And bzip2, mcg, hmmer,
>>> libquantum are the top four differences[1]. Note that bigger is better in
>>> specint test.
>>>
>>> In order to make sure the above results, I retest these four testcases in
>>> reportable way(reference the command in the end). The result[2] show that
>>> libquantum decrease -2.09% after ILP32 enabled and aarch32 on. I think it is in
>>> significant.
>>>
>>> The result of lmbench is not stable in my board. I plan to dig it later.
>>>
>>> [1] The following test result is tested through --size=ref --iterations=3.
>>> 1.1 Test when aarch32_el0 is enabled.
>>> ILP32 disabled base line
>>> 400.perlbench 100.00% 100%
>>> 401.bzip2 99.35% 100%
>>> 403.gcc 100.26% 100%
>>> 429.mcf 102.75% 100%
>>> 445.gobmk 100.00% 100%
>>> 456.hmmer 95.66% 100%
>>> 458.sjeng 100.00% 100%
>>> 462.libquantum 100.00% 100%
>>> 471.omnetpp 100.59% 100%
>>> 473.astar 99.66% 100%
>>> 483.xalancbmk 99.10% 100%
>>>
>>> 1.2 Test when aarch32_el0 is disabled
>>> ILP32 disabled base line
>>> 400.perlbench 100.22% 100%
>>> 401.bzip2 100.95% 100%
>>> 403.gcc 100.20% 100%
>>> 429.mcf 100.76% 100%
>>> 445.gobmk 100.36% 100%
>>> 456.hmmer 97.94% 100%
>>> 458.sjeng 99.73% 100%
>>> 462.libquantum 98.72% 100%
>>> 471.omnetpp 100.86% 100%
>>> 473.astar 99.15% 100%
>>> 483.xalancbmk 100.08% 100%
>>>
>>> [2] The following test result is tested through: runspec --config=my.cfg --size=test,train,ref --noreportable --tune=base,peak --iterations=3 bzip2 mcf hmmer libquantum
>>> 2.1 Test when aarch32_el0 is enabled.
>>> ILP32_enabled base line
>>> 401.bzip2 100.82% 100%
>>> 429.mcf 100.18% 100%
>>> 456.hmmer 99.64% 100%
>>> 462.libquantum 97.91% 100%
>>>
>>> Regards
>>>
>>> Bamvor
>>>
>>> On 2016/10/28 20:46, Yury Norov wrote:
>>>> [Add Steve Ellcey, thanks for testing on ThunderX]
>>>>
>>>> Lmbench-3.0-a9 testing is performed on ThunderX machine to check that
>>>> ILP32 series does not add performance regressions for LP64. Test
>>>> summary is in the table below. Our measurements doesn't show
>>>> significant performance regression of LP64 if ILP32 code is merged,
>>>> both enabled or disabled.
>>>>
>>>> ILP32 enabled ILP32 disabled Standard Kernel
>>>> null syscall 0.1066 0.1121 0.1121
>>>> 95.09% 100.00%
>>>>
>>>> stat 1.3947 1.3814 1.3864
>>>> 100.60% 99.64%
>>>>
>>>> fstat 0.4459 0.4344 0.4524
>>>> 98.56% 96.02%
>>>>
>>>> open/close 4.0606 4.0411 4.0453
>>>> 100.38% 99.90%
>>>>
>>>> read 0.4819 0.5014 0.5014
>>>> 96.11% 100.00%
>>>>
>>>> Tested with linux 4.8 because 4.9-rc1 is not fixed yet for ThunderX.
>>>> Other system details below.
>>>>
>>>> Yury.
>>>>
>>>> ubuntu at crb6:~$ uname -a
>>>> Linux crb6 4.8.0+ #3 SMP Thu Oct 27 11:01:32 PDT 2016 aarch64 aarch64 aarch64 GNU/Linux
>>>>
>>>> ubuntu at crb6:~$ cat /proc/meminfo
>>>> MemTotal: 132011948 kB
>>>> MemFree: 131442672 kB
>>>> MemAvailable: 130695764 kB
>>>> Buffers: 15696 kB
>>>> Cached: 88088 kB
>>>> SwapCached: 0 kB
>>>> Active: 82760 kB
>>>> Inactive: 41336 kB
>>>> Active(anon): 20880 kB
>>>> Inactive(anon): 8576 kB
>>>> Active(file): 61880 kB
>>>> Inactive(file): 32760 kB
>>>> Unevictable: 0 kB
>>>> Mlocked: 0 kB
>>>> SwapTotal: 128920572 kB
>>>> SwapFree: 128920572 kB
>>>> Dirty: 0 kB
>>>> Writeback: 0 kB
>>>> AnonPages: 20544 kB
>>>> Mapped: 19780 kB
>>>> Shmem: 9060 kB
>>>> Slab: 78804 kB
>>>> SReclaimable: 27372 kB
>>>> SUnreclaim: 51432 kB
>>>> KernelStack: 8336 kB
>>>> PageTables: 820 kB
>>>> NFS_Unstable: 0 kB
>>>> Bounce: 0 kB
>>>> WritebackTmp: 0 kB
>>>> CommitLimit: 194926544 kB
>>>> Committed_AS: 256324 kB
>>>> VmallocTotal: 135290290112 kB
>>>> VmallocUsed: 0 kB
>>>> VmallocChunk: 0 kB
>>>> AnonHugePages: 0 kB
>>>> ShmemHugePages: 0 kB
>>>> ShmemPmdMapped: 0 kB
>>>> CmaTotal: 0 kB
>>>> CmaFree: 0 kB
>>>> HugePages_Total: 0
>>>> HugePages_Free: 0
>>>> HugePages_Rsvd: 0
>>>> HugePages_Surp: 0
>>>> Hugepagesize: 2048 kB
>>>>
>>>> ubuntu at crb6:~$ cat /proc/cpuinfo
>>>> processor : 0
>>>> BogoMIPS : 200.00
>>>> Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 atomics
>>>> CPU implementer : 0x43
>>>> CPU architecture: 8
>>>> CPU variant : 0x1
>>>> CPU part : 0x0a1
>>>> CPU revision : 0
>>>>
>>>> processor : 1
>>>> BogoMIPS : 200.00
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>>>> CPU implementer : 0x43
>>>> CPU architecture: 8
>>>> CPU variant : 0x1
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>>>>
>>>> processor : 2
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>>>> CPU implementer : 0x43
>>>> CPU architecture: 8
>>>> CPU variant : 0x1
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>>>> processor : 3
>>>> BogoMIPS : 200.00
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>>>> CPU implementer : 0x43
>>>> CPU architecture: 8
>>>> CPU variant : 0x1
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>>>> processor : 4
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>>>>
>>>
>>
>