Bug #100132 Using optimal memory-barrier (in form of acquire/release) for event-mutex
Submitted: 7 Jul 2020 5:13 Modified: 22 Sep 2020 3:47
Reporter: Krunal Bauskar Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Server: InnoDB storage engine Severity:S5 (Performance)
Version:8.0.20 OS:Any
Assigned to: CPU Architecture:ARM
Tags: event-mutex, memory-barrier, performance

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Description:
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[7 Jul 2020 5:14] Krunal Bauskar 
arm benchmark

Attachment: arm_eventmutex.png (image/png, text), 70.49 KiB.
[7 Jul 2020 5:14] Krunal Bauskar 
x86 benchmark

Attachment: x86_eventmutex.png (image/png, text), 70.14 KiB.
[13 Jul 2020 14:37] Jakub Lopuszanski 
Proposal of a patch which provides provable correctness in C++14-compliant environment and performance on ARM

Attachment: seqcst_mutex.patch (application/octet-stream, text), 7.05 KiB.
[22 Jul 2020 9:19] Krunal Bauskar 
updated patch

Attachment: patch.bug100132 (application/octet-stream, text), 2.17 KiB.
[23 Jul 2020 12:51] Jakub Lopuszanski 
proposal based on m_waiters.exchange(..) used consistently

Attachment: rb.2 (application/octet-stream, text), 6.18 KiB.
[27 Jul 2020 7:03] Krunal Bauskar 
benchmark

Attachment: zipfian-x86.png (image/png, text), 129.72 KiB.
[27 Jul 2020 7:03] Krunal Bauskar 
benchmark

Attachment: uniform-x86.png (image/png, text), 128.43 KiB.
[27 Jul 2020 7:04] Krunal Bauskar 
benchmark

Attachment: zipfian-arm.png (image/png, text), 129.38 KiB.
[27 Jul 2020 7:04] Krunal Bauskar 
benchmark

Attachment: uniform-arm.png (image/png, text), 130.82 KiB.
[1 Aug 2020 7:09] Krunal Bauskar 
exchange arm benchmark

Attachment: arm-exchange.png (image/png, text), 98.76 KiB.
[1 Aug 2020 7:10] Krunal Bauskar 
exchange x86 benchmark

Attachment: x86-exchange.png (image/png, text), 101.55 KiB.
[4 Aug 2020 8:11] Jakub Lopuszanski 
Data for Proposal-1 and Proposal-2 ARM zipfian

Attachment: summary-arm-zipfian.png (image/png, text), 12.40 KiB.