| From: | Thomas Munro <thomas(dot)munro(at)gmail(dot)com> |
|---|---|
| To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
| Cc: | PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org> |
| Subject: | Re: We're leaking predicate locks in HEAD |
| Date: | 2019-05-08 03:30:32 |
| Message-ID: | CA+hUKGLhC5u5EsKJRD5LDjo4t1W8s3ied2u9WOykS1ud4ugQ+Q@mail.gmail.com |
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| Lists: | pgsql-hackers |
On Wed, May 8, 2019 at 6:56 AM Thomas Munro <thomas(dot)munro(at)gmail(dot)com> wrote:
> On Wed, May 8, 2019 at 5:46 AM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> > I'd have to say that my first suspicion falls on bb16aba50 ...
>
> Investigating.
Reproduced here. Once the system reaches a state where it's leaking
(which happens only occasionally for me during installcheck-parallel),
it keeps leaking for future SSI transactions. The cause is
SxactGlobalXmin getting stuck. The attached fixes it for me. I can't
remember why on earth I made that change, but it is quite clearly
wrong: you have to check every transaction, or you might never advance
SxactGlobalXmin.
--
Thomas Munro
https://enterprisedb.com
| Attachment | Content-Type | Size |
|---|---|---|
| 0001-Fix-SxactGlobalXmin-tracking.patch | application/octet-stream | 1.2 KB |
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