Note that I'm not comparing to HEAD in the above tests, but with the new options desactivated, which should be more or less comparable to current HEAD, i.e. there is no sorting nor flushing done, but this is not strictly speaking HEAD behavior. Probably I should get some figures with HEAD as well to check the "more or less" assumption.

Just for answering myself on this point, I tried current HEAD vs patch v4 with sort OFF + flush OFF: the figures are indeed quite comparable (see below), so although the internal implementation is different, the performance when both options are off is still a reasonable approximation of the performance without the patch, as I was expecting. What patch v4 still does with OFF/OFF which is not done by HEAD is balancing writes among tablespaces, but there is only one disk on these tests so it does not matter.

tps & stddev full speed:

                            HEAD         OFF/OFF

 tiny 1 client          727 +- 227     221 +- 246
 small 1 client         158 +- 316     158 +- 325
 medium 1 client        148 +- 285     157 +- 326
 tiny 4 clients        2088 +- 786    2074 +- 699
 small 4 clients        192 +- 648     188 +- 560
 medium 4 clients       220 +- 654     220 +- 648

percent of late transactions:

                            HEAD       OFF/OFF

 tiny 4 clients 100 tps      6.31        6.67
 small 4c 100 tps           35.68       35.23
 medium 4c 100 tps          37.38       38.00
 tiny 4c 200 tps             9.06        9.10
 small 4c 200 tps           51.65       51.16
 medium 4c 200 tps          51.35       50.20
 tiny 4 clients 400 tps     11.4        10.5
 small 4 clients 400 tps    66.4        67.6

--
Fabien.


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