On 4/8/22 21:02, Andres Freund wrote:
> Hi,
>
> On 2022-04-08 19:27:58 -0500, Justin Pryzby wrote:
>> On Thu, Apr 07, 2022 at 10:10:21AM -0700, Andres Freund wrote:
>>> On 2022-04-06 11:03:37 -0400, Andrew Dunstan wrote:
>>>> On 3/30/22 20:26, Andres Freund wrote:
>>>>> Could you try using dash to invoke configure here, and whether it makes configure faster?
>>>> I got weird failures re libxml/parser.h when I tried with dash. See
>>>> <https://cirrus-ci.com/task/5963254039052288> (It would be nice if we
>>>> could see config.log on failure.)
>>> Since dash won't help us to get the build time down sufficiently, and the
>>> tests don't pass without a separate build tree, I looked at what makes
>>> config/prep_buildtree so slow.
>>>
>>> It's largely just bad code. The slowest part are spawning one expr and mkdir
>>> -p for each directory. One 'cmp' for each makefile doesn't help either.
>>>
>>> The expr can be replaced with
>>> subdir=${item#$sourcetree}
>>> that's afaics posix syntax ([1]), not bash.
>>>
>>> Spawning one mkdir for each directory can be replaced by a single mkdir
>>> invocation with all the directories. On my linux workstation that gets the
>>> time for the first loop down from 1005ms to 38ms, really.
>> Even better?
>>
>> (cd "$sourcetree" && find . -print |grep -E '/Makefile$|/GNUmakefile$' |grep -v "$sourcetree/doc/src/sgml/images/"
|xargstar c) |
>> (cd "$buildtree" && tar x)
> Don't think we depend on tar for building, at the moment. But yes, it'd be
> faster... Tar is certainly a smaller dependency than perl, not sure if there's
> any relevant platform without it?
>
>
Couple of things here.
1. The second grep should lose "$sourcetree" I think.
2. Isn't this going to be a change in behaviour in that it will copy
rather than symlinking the Makefiles? That is in fact the default
behaviour of msys2's 'ln -s', as I pointed out upthread, but I don't
think it's what we really want, especially in the general case. If you
modify the Makefile and you're using a vpath you want to see the change
reflected in your vpath.
cheers
andrew
--
Andrew Dunstan
EDB: https://www.enterprisedb.com
