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Tom Lane 8a30cc2127 Make the planner estimate costs for nestloop inner indexscans on the basis ... that the Mackert-Lohmann formula applies across all the repetitions of the nestloop, not just each scan independently. We use the M-L formula to estimate the number of pages fetched from the index as well as from the table; that isn't what it was designed for, but it seems reasonably applicable anyway. This makes large numbers of repetitions look much cheaper than before, which accords with many reports we've received of overestimation of the cost of a nestloop. Also, change the index access cost model to charge random_page_cost per index leaf page touched, while explicitly not counting anything for access to metapage or upper tree pages. This may all need tweaking after we get some field experience, but in simple tests it seems to be giving saner results than before. The main thing is to get the infrastructure in place to let cost_index() and amcostestimate functions take repeated scans into account at all. Per my recent proposal. Note: this patch changes pg_proc.h, but I did not force initdb because the changes are basically cosmetic --- the system does not look into pg_proc to decide how to call an index amcostestimate function, and there's no way to call such a function from SQL at all.		20 years ago
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adt	Make the planner estimate costs for nestloop inner indexscans on the basis	20 years ago
cache	Further minor simplification of relcache startup: don't need a static	20 years ago
error	Update copyright for 2006. Update scripts.	20 years ago
fmgr	Make PG_MODULE_MAGIC required in shared libraries that are loaded into	20 years ago
hash	Update copyright for 2006. Update scripts.	20 years ago
init	Simplify relcache startup sequence. With the new design of InitPostgres	20 years ago
mb	Magic blocks don't do us any good unless we use 'em ... so install one	20 years ago
misc	Increase the default value of cpu_index_tuple_cost from 0.001 to 0.005.	20 years ago
mmgr	Back out RESET CONNECTION until there is more discussion.	20 years ago
resowner	Eliminate ajust scan code. Since concurrent GiST it doesn't	20 years ago
sort	Tweak writetup_heap/readtup_heap to avoid storing the tuple identity	20 years ago
time	Update copyright for 2006. Update scripts.	20 years ago
.cvsignore	Cleanup to ensure good state of derived files in tarballs.	26 years ago
Gen_fmgrtab.sh	Update copyright for 2006. Update scripts.	20 years ago
Makefile	Invent ResourceOwner mechanism as per my recent proposal, and use it to	22 years ago