Re: [HACKERS] Re: [GSOC 17] Eliminate O(N^2) scaling fromrw-conflict tracking in serializable transactions - Mailing list pgsql-hackers

From Alvaro Herrera
Subject Re: [HACKERS] Re: [GSOC 17] Eliminate O(N^2) scaling fromrw-conflict tracking in serializable transactions
Date
Msg-id 20170602150846.a66dhsfnsru7fau5@alvherre.pgsql
Whole thread Raw
In response to Re: [HACKERS] Re: [GSOC 17] Eliminate O(N^2) scaling fromrw-conflict tracking in serializable transactions  ("Mengxing Liu" <liu-mx15@mails.tsinghua.edu.cn>)
Responses Re: [HACKERS] Re: [GSOC 17] Eliminate O(N^2) scaling fromrw-conflict tracking in serializable transactions  (Kevin Grittner <kgrittn@gmail.com>)
List pgsql-hackers
Mengxing Liu wrote:
> Hi,  Alvaro and Kevin.
> 
> > Anyway, this is just my analysis. 
> > So I want to hack the PG and count the conflict lists' size of transactions. That would be more accurate.
> 
> In the last week, I hacked the PG to add an additional thread to count RWConflict list lengths. 
> And tune the benchmark to get more conflict. But the result is still not good.

Kevin mentioned during PGCon that there's a paper by some group in
Sydney that developed a benchmark on which this scalability problem
showed up very prominently.  I think your first step should be to
reproduce their results -- my recollection is that Kevin says you
already know that paper, so please dedicate some time to analyze it and
reproduce their workload.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services



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