G
George Potemkin
Guest
And new tests did found some inconsistency. If I set the high value of the -lruskips online using promon and then return it back to zero the behaviour of Progress sessions will not be the same as just after db startup with -lruskips 0. I used promon itself to access the blocks. Any action in promon ("U"pdate, "S"ample, "Z"ero and even "R"epeat?!) reads the ACO object blocks - one block per data area including "Control Area". And, by the way, the queries of any VSTs do the same. It's VERY unfortunate that these blocks are on the LRU chain. So in sports db promon's actions will read 7 blocks (and will create 7 BHT and 7 LRU latch locks). We can create db accesses and check their latch locks without leaving the "Activity: Latch Counts" screen. After the changing the -lruskips forth and back these actions will not lock LRU latch anymore. Really it's excellent news! But I would like to understand if it's a real thing or just a "mirage". ;-)
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