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[git.ikiwiki.info.git] / doc / todo / should_optimise_pagespecs.mdwn

diff --git a/doc/todo/should_optimise_pagespecs.mdwn b/doc/todo/should_optimise_pagespecs.mdwn
index 9d2611249ed42c272c5b380b5349d3fcb8784e8f..1594dcee76eb2e1a3fe66b3a2b5452d3c0b8b9b9 100644 (file)
--- a/doc/todo/should_optimise_pagespecs.mdwn
+++ b/doc/todo/should_optimise_pagespecs.mdwn
@@ -113,6 +113,18 @@ In saveindex it still or'd together the depends list, but the `{depends}`
 field seems only useful for backwards compatability (ie, ikiwiki-transition
 uses it still), and otherwise just bloats the index.
 
 field seems only useful for backwards compatability (ie, ikiwiki-transition
 uses it still), and otherwise just bloats the index.
 

+> If it's acceptable to declare that downgrading IkiWiki requires a complete
+> rebuild, I'm happy with that. I'd prefer to keep the (simple form of the)
+> transition done automatically during a load/save cycle, rather than
+> requiring ikiwiki-transition to be run; we should probably say in NEWS
+> that the performance increase won't fully apply until the next
+> rebuild. --[[smcv]]
+
+>> It is acceptable not to support downgrades.
+>> I don't think we need a NEWS file update since any sort of refresh,
+>> not just a full rebuild, will cause the indexdb to be loaded and saved,
+>> enabling the optimisation. --[[Joey]] 
+

 Is an array the right data structure? `add_depends` has to loop through the
 array to avoid dups, it would be better if a hash were used there. Since
 inline (and other plugins) explicitly add all linked pages, each as a
 Is an array the right data structure? `add_depends` has to loop through the
 array to avoid dups, it would be better if a hash were used there. Since
 inline (and other plugins) explicitly add all linked pages, each as a


@@ -128,17 +140,46 @@ to avoid..
 > and the hash for individual page names.  To make this work you need to adjust the
 > API so it knows which you're adding.  -- [[Will]]
 
 > and the hash for individual page names.  To make this work you need to adjust the
 > API so it knows which you're adding.  -- [[Will]]
 

+> I wasn't thinking about a lookup hash, just a dedup hash, FWIW.
+> --[[Joey]]
+
+>> I was under the impression from previous code review that you preferred
+>> to represent unordered sets as lists, rather than hashes with dummy
+>> values. If I was wrong, great, I'll fix that and it'll probably go
+>> a bit faster. --[[smcv]]
+
+>>> It depends, really. And it'd certianly make sense to benchmark such a
+>>> change. --[[Joey]] 
+

 Also, since a lot of places are calling add_depends in a loop, it probably
 makes sense to just make it accept a list of dependencies to add. It'll be
 marginally faster, probably, and should allow for better optimisation
 when adding a lot of depends at once.
 
 Also, since a lot of places are calling add_depends in a loop, it probably
 makes sense to just make it accept a list of dependencies to add. It'll be
 marginally faster, probably, and should allow for better optimisation
 when adding a lot of depends at once.
 

+> That'd be an API change; perhaps marginally faster, but I don't
+> see how it would allow better optimisation if we're de-duplicating
+> anyway? --[[smcv]]
+
+>> Well, I was thinking that it might be sufficient to build a `%seen`
+>> hash of dependencies inside `add_depends`, if the places that call
+>> it lots were changed to just call it once. Of course the only way to
+>> tell is benchmarking. --[[Joey]] 
+

 In Render.pm, we now have a triply nested loop, which is a bit
 scary for efficiency. It seems there should be a way to
 rework this code so it can use the optimised `pagespec_match_list`,
 and/or hoist some of the inner loop calculations (like the `pagename`)
 out.
 
 In Render.pm, we now have a triply nested loop, which is a bit
 scary for efficiency. It seems there should be a way to
 rework this code so it can use the optimised `pagespec_match_list`,
 and/or hoist some of the inner loop calculations (like the `pagename`)
 out.
 

+> I don't think the complexity is any greater than it was: I've just
+> moved one level of "loop" out of the generated Perl, to be
+> in visible code. I'll see whether some of it can be hoisted, though.
+> --[[smcv]]
+
+>> The call to `pagename` is the only part I can see that's clearly
+>> run more often than before. That function is pretty inexpensive, but..
+>> --[[Joey]]
+

 Very good catch on img/meta using the wrong dependency; verified in the wild!
 (I've cherry-picked those bug fixes.)
 
 Very good catch on img/meta using the wrong dependency; verified in the wild!
 (I've cherry-picked those bug fixes.)