On Tue, Apr 07, 2020 at 08:40:30AM -0400, James Coleman wrote:
On Tue, Apr 7, 2020 at 12:25 AM Justin Pryzby <pry...@telsasoft.com> wrote:
On Mon, Apr 06, 2020 at 09:57:22PM +0200, Tomas Vondra wrote:
> I've pushed the fist part of this patch series - I've reorganized it a
I scanned through this again post-commit. Find attached some suggestions.
Shouldn't non-text explain output always show both disk *and* mem, including
zeros ?
Could you give more context on this? Is there a standard to follow?
Regular sort nodes only ever report one type, so there's not a good
parallel there.
Should "Pre-sorted Groups:" be on a separate line ?
| Full-sort Groups: 1 Sort Method: quicksort Memory: avg=28kB peak=28kB
Pre-sorted Groups: 1 Sort Method: quicksort Memory: avg=30kB peak=30kB
I'd originally had that, but Tomas wanted it to be more compact. It's
easy to adjust though if the consensus changes on that.
I'm OK with changing the format if there's a consensus. The current
format seemed better to me, but I'm not particularly attached to it.
And, should it use two spaces before "Sort Method", "Memory" and "Pre-sorted
Groups"? I think you should maybe do that instead of the "semicolon
separator". I think "two spaces" makes sense, since the units are different,
similar to hash buckets and normal sort node.
"Buckets: %d Batches: %d Memory Usage: %ldkB\n",
appendStringInfo(es->str, "Sort Method: %s %s: %ldkB\n",
Note, I made a similar comment regarding two spaces for explain(WAL) here:
https://www.postgresql.org/message-id/20200402054120.GC14618%40telsasoft.com
And Peter E seemed to dislike that, here:
https://www.postgresql.org/message-id/ef8c966f-e50a-c583-7b1e-85de6f4ca0d3%402ndquadrant.com
I read through that subthread, and the ending seemed to be Peter
wanting things to be unified. Was there a conclusion beyond that?
Yeah, I don't think there was a clear consensus :-(
Also, you're showing:
ExplainPropertyInteger("Maximum Sort Space Used", "kB",
groupInfo->maxMemorySpaceUsed, es);
But in show_hash_info() and show_hashagg_info(), and in your own text output,
that's called "Peak":
ExplainPropertyInteger("Peak Memory Usage", "kB", memPeakKb, es);
ExplainPropertyInteger("Peak Memory Usage", "kB",
spacePeakKb, es);
Yes, that's a miss and should be fixed.
Will fix.
regards
--
Tomas Vondra http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
