Bugs item #1650205, was opened at 2007-02-01 23:03 Message generated for change (Comment added) made by sf-robot You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=482468&aid=1650205&group_id=56967
Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: PF/runtime Group: (zombie: Pathfinder 0.16) >Status: Closed Resolution: Fixed Priority: 3 Private: No Submitted By: Peter Boncz (boncz) Assigned to: Sjoerd Mullender (sjoerd) Summary: PF: empty pages never reused Initial Comment: I was toying a bit with bulk updates /data/home/boncz/bench/mod.xq doing mod:addbulk() followed by mod:del() thus, insert 14 pages, and then delete all those nodes again. if done repeatedly, one notices that the document keeps growing by 14 pages each update. that is, new pages are allocated; the data on them is subsequently deleted, but the pages are not freed, *nor* are they re-used. it turns out that the insert code just checks whether the hole *on-the-page* is sufficiently large. As the insert requires 14 pages, this is never the case. Therefore, it decides to insert new pages. Continuing along these lines, if our insert point happens to be very near the page boundary (say fully at the end), and we have an access pattern that reatedly inserts "as first" there, each such insert of a single node will cause the insertion of a new page!! thus, I would propose the following: - in deletes, reclaim fully free pages - if less than a full new page is missing, check if the next still not reclaimed old page has enough free space (at the end). Use movedata to make room on that page. that should strongly improve the fill degree of the rid table in many scenarios. ---------------------------------------------------------------------- >Comment By: SourceForge Robot (sf-robot) Date: 2010-04-08 02:20 Message: This Tracker item was closed automatically by the system. It was previously set to a Pending status, and the original submitter did not respond within 365 days (the time period specified by the administrator of this Tracker). ---------------------------------------------------------------------- Comment By: Peter Boncz (boncz) Date: 2009-04-07 08:31 Message: will not be fixed, will disappear eventually in the new MonetDB5 runtime ---------------------------------------------------------------------- Comment By: Stefan Manegold (stmane) Date: 2008-02-10 13:18 Message: Logged In: YES user_id=572415 Originator: NO tagged as "PF" in subject ---------------------------------------------------------------------- Comment By: Stefan Manegold (stmane) Date: 2007-06-04 18:40 Message: Logged In: YES user_id=572415 Originator: NO Peter, Sjoerd, is this one still an open issues after all the recent XQUF code changes/improvements? Stefan ---------------------------------------------------------------------- Comment By: Sjoerd Mullender (sjoerd) Date: 2007-02-19 12:12 Message: Logged In: YES user_id=43607 Originator: NO Lowered priority. ---------------------------------------------------------------------- Comment By: Sjoerd Mullender (sjoerd) Date: 2007-02-13 08:56 Message: Logged In: YES user_id=43607 Originator: NO Newly empty pages are now returned to the system. The other part of the proposal needs more thought and work, so I'll keep this report open. ---------------------------------------------------------------------- Comment By: Martin Kersten (mlkersten) Date: 2007-02-09 17:14 Message: Logged In: YES user_id=490798 Originator: NO tag for filtering ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=482468&aid=1650205&group_id=56967 ------------------------------------------------------------------------------ Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev _______________________________________________ Monetdb-bugs mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/monetdb-bugs
