| From: | David Gilman <dgilman(at)gilslotd(dot)com> |
|---|---|
| To: | Justin Pryzby <pryzby(at)telsasoft(dot)com> |
| Cc: | David Gilman <davidgilman1(at)gmail(dot)com>, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, pgsql-hackers(at)lists(dot)postgresql(dot)org, thomas(dot)munro(at)gmail(dot)com |
| Subject: | Re: Warn when parallel restoring a custom dump without data offsets |
| Date: | 2020-05-25 21:55:26 |
| Message-ID: | 20200525215526.t7dqywfywxzmlpbu@dar.local |
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| Thread: | |
| Lists: | pgsql-hackers |
The earlier patches weren't applying because I had "git config
diff.noprefix true" set globally and that was messing up the git
format-patch output.
On Mon, May 25, 2020 at 01:54:29PM -0500, David Gilman wrote:
> And I misunderstood how bad it was. I thought it was reading little
> header structs off the disk but it's actually reading the entire table
> (see _skipData). So you're quadratically rereading entire tables and
> thrashing your cache. Oops.
I changed _skipData to fseeko() instead of fread() when possible to cut
down on this thrashing further.
--
David Gilman :DG<
https://gilslotd.com
| Attachment | Content-Type | Size |
|---|---|---|
| 0001-Remove-unused-seek-check-in-tar-dump-format.patch | text/x-diff | 1.1 KB |
| 0002-Skip-tables-in-pg_restore-by-seeking-instead-of-read.patch | text/x-diff | 1.5 KB |
| 0003-Scan-all-TOCs-when-restoring-a-custom-dump-file-with.patch | text/x-diff | 3.7 KB |
| 0004-Add-integration-test-for-out-of-order-TOC-requests-i.patch | text/x-diff | 11.4 KB |
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