-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hedley Roos wrote: >>> object_implements |KeywordIndex |0.2172234| 4.6 >> This is clearly not the same issue as the other KeywordIndexes: in >> fact, I am astonished that anybody would be using a KeywordIndex for >> this at all. I would suspect that the real problem here is in the >> appliation, rather than the index itself. > > The app is Plone :)
I don't know how Plone computes the values here (are they actual interface objects, or their monikers), nor how it is queried. I am suspicious that there is some query-time bogosity, however. >>> portal_type |FieldIndex |0.0025984| 384.84 >> This one is surprising: its performance should be pretty similar to the >> other FieldIndexes (e.g., 'review_state') which map a controlled >> vocabulary onto the entire corpus. Was the query different than >> 'review_state' (e.g., multi-valued vs. single-valued)? > > portal_type queries are usually multivalued in Plone. What are the use cases for that? >>> sourceUID |FieldIndex |0.0004886| 2046.31 >> Probably bogus, but I don't know how it is used. > > > Plone's reference_catalog I'm betting that using a catalog at all is a flawed choice. >>> UID |FieldIndex |0.0003070| 3257.1 >> Note that this is the worst-case scenario for a FieldIndex: there is >> exactly one value for every key. This shouldn't be "indexed" at all, in >> fact, beyond a simple BTree (UID -> rid). > > I've never even thought of that. Perhaps the catalog is used to > present a familiar API. > >>> targetUID |FieldIndex |0.0002287| 4372.12 >> I don't know what this one is used for, but it should probably be >> scrapped as well. > > More reference_catalog. > >>> exact_getUserId |FieldIndex |0.0001931| 5177.79 >>> exact_getUserName |FieldIndex |0.0001816| 5504.39 >> I don't know how the application uses either of those indexes, but they >> are almost certainly bogus in any normal catalog. > > Membrane and remember. They're currently tied to Plone but efforts are > being made to make them work with CMF. > >>> relationship |FieldIndex |0.0000822| 12153.1 >>> id |FieldIndex |0.0000822| 12161.81 >>> end |DateIndex |0.0000623| 16027.48 >>> getGroups |FieldIndex |0.0000278| 35973.45 >> This is almost certainly bogus: FieldIndex is not supposed to be used >> with multi-valued terms. > > Plone stuff, but I am intrigued by your statement. Why can FieldIndex > not be used with multi-valued terms? Because FieldIndex is designed for either exact-match queries or range queries: range queries are obviously impossible for a 'getGroups' method, and exact-match is nearly as dubious. I would have expected this to be a KeywordIndex, if it needed indexing at all. >>> Subject |KeywordIndex |0.0000253| 39413.57 >> This is the use-case for which KeywordIndex is designed. Was the query >> just a single term, by chance? > > The simplest term is a list with only a single term (not counting the > trivial case). It should be worse with more terms right? I am reasonably confident that multi-valued queries against either FieldIndexes or KeywordIndexes will perform worse than single-valued queries against the same index. >>> Title |ZCTextIndex |0.0000128| 77809.46 >> This should be removed: there is no valid use case for doing a >> full-text search restricted only to the title. > > Plone specific. No, still bogus. This is an egregiously stupid choice, with *large* indexing-time downsides. >>> Description |ZCTextIndex |0.0000116| 86241.39 >> Again, should be removed. > > Again, Plone specific :) Again, egregiously bogus. >>> getEmail |ZCTextIndex |0.0000113| 87849.05 >> Should *definitely* be removed: how can you do full-text search on an >> e-mail address? > > I think membrane is responsible for this, but you're right. > > >>> SearchableText |TextIndex |0.0000113| 88466.69 >> Where did this one come from? The 'SearchableText' above is a ZCTextIndex. > > Membrane! > > Kinda pointless for me to continue since this is turning into a > Plone-specific discussion on zope-dev. But at least the whole exercise > has forced us to look in detail into how all these indexes affect > performance with a zodb with many many objects. > > Roche investigated Tesdal's queryplan today end it seems to solve > nearly all our performance problems. He'll have to elaborate. Ripping out stupid indexes is one of the first things I do to optimize a client's badly-performing Plone site. Tres. - -- =================================================================== Tres Seaver +1 540-429-0999 [EMAIL PROTECTED] Palladion Software "Excellence by Design" http://palladion.com -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFJGHHu+gerLs4ltQ4RAoDgAJ9sjGoOG2KftnqFIbVxFy0sNk8EDwCfaSbH ouY7+FnSbSJvYSBtI//31ZY= =3SeB -----END PGP SIGNATURE----- _______________________________________________ Zope-Dev maillist - Zope-Dev@zope.org http://mail.zope.org/mailman/listinfo/zope-dev ** No cross posts or HTML encoding! ** (Related lists - http://mail.zope.org/mailman/listinfo/zope-announce http://mail.zope.org/mailman/listinfo/zope )
