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docs: outdated reference to recursive expression evaluation 4+ messages / 2 participants [nested] [flat]
Commits from this thread: 2018-12-10 0f9fd7419a 001bb9f3ed 62999b9325 e60122b54d 552c310ba4 3af726a1f3 Add stack depth checks to key recursive functions in backend/nodes/*.c. 2018-12-10 e28649a67f Doc: remove obsolete reference to recursive expression evaluation.
* docs: outdated reference to recursive expression evaluation @ 2018-12-08 12:21 John Naylor <jcnaylor@gmail.com> 2018-12-08 16:30 ` Re: docs: outdated reference to recursive expression evaluation Tom Lane <tgl@sss.pgh.pa.us> 0 siblings, 1 reply; 4+ messages in thread From: John Naylor @ 2018-12-08 12:21 UTC (permalink / raw) To: pgsql-hackers In confg.sgml, in the section about max_stack_depth, there's this sentence: "The safety margin is needed because the stack depth is not checked in every routine in the server, but only in key potentially-recursive routines such as expression evaluation." Since the change in expression evaluation in v10, there's probably a better example of recursive routines, but I'm not sure what that would be. -John Naylor ^ permalink raw reply [nested|flat] 4+ messages in thread
* Re: docs: outdated reference to recursive expression evaluation 2018-12-08 12:21 docs: outdated reference to recursive expression evaluation John Naylor <jcnaylor@gmail.com> @ 2018-12-08 16:30 ` Tom Lane <tgl@sss.pgh.pa.us> 2018-12-10 14:55 ` Re: docs: outdated reference to recursive expression evaluation John Naylor <jcnaylor@gmail.com> 0 siblings, 1 reply; 4+ messages in thread From: Tom Lane @ 2018-12-08 16:30 UTC (permalink / raw) To: John Naylor <jcnaylor@gmail.com>; +Cc: pgsql-hackers John Naylor <jcnaylor@gmail.com> writes: > In confg.sgml, in the section about max_stack_depth, there's this sentence: > "The safety margin is needed because the stack depth is not checked in > every routine in the server, but only in key potentially-recursive > routines such as expression evaluation." > Since the change in expression evaluation in v10, there's probably a > better example of recursive routines, but I'm not sure what that would > be. We could say "expression compilation" and it'd still be valid. Or just drop the last four words altogether. I don't think we want to expend the verbiage to be more precise here, since it's only a tangential point. BTW, while looking at this I noted that copyfuncs.c has a check_stack_depth call but outfuncs, readfuncs, equalfuncs don't. Surely that's not good. regards, tom lane ^ permalink raw reply [nested|flat] 4+ messages in thread
* Re: docs: outdated reference to recursive expression evaluation 2018-12-08 12:21 docs: outdated reference to recursive expression evaluation John Naylor <jcnaylor@gmail.com> 2018-12-08 16:30 ` Re: docs: outdated reference to recursive expression evaluation Tom Lane <tgl@sss.pgh.pa.us> @ 2018-12-10 14:55 ` John Naylor <jcnaylor@gmail.com> 2018-12-10 15:44 ` Re: docs: outdated reference to recursive expression evaluation Tom Lane <tgl@sss.pgh.pa.us> 0 siblings, 1 reply; 4+ messages in thread From: John Naylor @ 2018-12-10 14:55 UTC (permalink / raw) To: Tom Lane <tgl@sss.pgh.pa.us>; +Cc: pgsql-hackers On 12/8/18, Tom Lane <tgl@sss.pgh.pa.us> wrote: > John Naylor <jcnaylor@gmail.com> writes: >> In confg.sgml, in the section about max_stack_depth, there's this >> sentence: >> "The safety margin is needed because the stack depth is not checked in >> every routine in the server, but only in key potentially-recursive >> routines such as expression evaluation." > >> Since the change in expression evaluation in v10, there's probably a >> better example of recursive routines, but I'm not sure what that would >> be. > > We could say "expression compilation" and it'd still be valid. Or just > drop the last four words altogether. I don't think we want to expend the > verbiage to be more precise here, since it's only a tangential point. I'm inclined to agree. If you like, here's a patch to leave out the example. -John Naylor Attachments:^ permalink raw reply [nested|flat] 4+ messages in threadremove-reference-to-expr-eval.patch (text/x-patch, 1.2K) download
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index fc4f17be41..4a7121a51f 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -1675,12 +1675,11 @@ include_dir 'conf.d' enforced by the kernel (as set by <literal>ulimit -s</literal> or local equivalent), less a safety margin of a megabyte or so. The safety margin is needed because the stack depth is not checked in every - routine in the server, but only in key potentially-recursive routines - such as expression evaluation. The default setting is two - megabytes (<literal>2MB</literal>), which is conservatively small and - unlikely to risk crashes. However, it might be too small to allow - execution of complex functions. Only superusers can change this - setting. + routine in the server, but only in key potentially-recursive routines. + The default setting is two megabytes (<literal>2MB</literal>), which + is conservatively small and unlikely to risk crashes. However, + it might be too small to allow execution of complex functions. + Only superusers can change this setting. </para> <para>
* Re: docs: outdated reference to recursive expression evaluation 2018-12-08 12:21 docs: outdated reference to recursive expression evaluation John Naylor <jcnaylor@gmail.com> 2018-12-08 16:30 ` Re: docs: outdated reference to recursive expression evaluation Tom Lane <tgl@sss.pgh.pa.us> 2018-12-10 14:55 ` Re: docs: outdated reference to recursive expression evaluation John Naylor <jcnaylor@gmail.com> @ 2018-12-10 15:44 ` Tom Lane <tgl@sss.pgh.pa.us> 0 siblings, 0 replies; 4+ messages in thread From: Tom Lane @ 2018-12-10 15:44 UTC (permalink / raw) To: John Naylor <jcnaylor@gmail.com>; +Cc: pgsql-hackers John Naylor <jcnaylor@gmail.com> writes: > On 12/8/18, Tom Lane <tgl@sss.pgh.pa.us> wrote: >> We could say "expression compilation" and it'd still be valid. Or just >> drop the last four words altogether. I don't think we want to expend the >> verbiage to be more precise here, since it's only a tangential point. > I'm inclined to agree. If you like, here's a patch to leave out the example. Pushed to HEAD (didn't seem worth back-patching, though). regards, tom lane ^ permalink raw reply [nested|flat] 4+ messages in thread
end of thread, other threads:[~2018-12-10 15:44 UTC | newest] Thread overview: 4+ messages (download: mbox mbox.gz follow: Atom feed) -- links below jump to the message on this page -- 2018-12-08 12:21 docs: outdated reference to recursive expression evaluation John Naylor <jcnaylor@gmail.com> 2018-12-08 16:30 ` Tom Lane <tgl@sss.pgh.pa.us> 2018-12-10 14:55 ` John Naylor <jcnaylor@gmail.com> 2018-12-10 15:44 ` Tom Lane <tgl@sss.pgh.pa.us>
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