On Jan 4, 2012, at 2:02 PM, Kevin Grittner wrote: > Jim Nasby <j...@nasby.net> wrote: >> Here's output from our largest OLTP system... not sure exactly how >> to interpret it, so I'm just providing the raw data. This spans >> almost exactly 1 month. > > Those number wind up meaning that 18% of the 256-byte blocks (1024 > transactions each) were all commits. Yikes. That pretty much > shoots down Robert's idea of summarized CLOG data, I think.
Here's another data point. This is for a londiste slave of what I posted earlier. Note that this slave has no users on it. 054A 654 054B 835 054C 973 054D 1020 054E 1012 054F 1022 0550 284 And these clog files are from Sep 15-30... I believe that's the period when we were building this slave, but I'm not 100% certain. 04F0 194 04F1 253 04F2 585 04F3 243 04F4 176 04F5 164 04F6 358 04F7 505 04F8 168 04F9 180 04FA 369 04FB 318 04FC 236 04FD 437 04FE 242 04FF 625 0500 222 0501 139 0502 174 0503 91 0504 546 0505 220 0506 187 0507 151 0508 199 0509 491 050A 232 050B 170 050C 191 050D 414 050E 557 050F 231 0510 173 0511 159 0512 436 0513 789 0514 354 0515 157 0516 187 0517 333 0518 599 0519 483 051A 300 051B 512 051C 713 051D 422 051E 291 051F 596 0520 785 0521 825 0522 484 0523 238 0524 151 0525 190 0526 256 0527 403 0528 551 0529 757 052A 837 052B 418 052C 256 052D 161 052E 254 052F 423 0530 469 0531 757 0532 627 0533 325 0534 224 0535 295 0536 290 0537 352 0538 561 0539 565 053A 833 053B 756 053C 485 053D 276 053E 241 053F 270 0540 334 0541 306 0542 700 0543 821 0544 402 0545 199 0546 226 0547 250 0548 354 0549 587 This is for a slave of that database that does have user activity: 054A 654 054B 835 054C 420 054D 432 054E 852 054F 666 0550 302 0551 243 0552 600 0553 295 0554 617 0555 504 0556 232 0557 304 0558 580 0559 156 -- Jim C. Nasby, Database Architect j...@nasby.net 512.569.9461 (cell) http://jim.nasby.net -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers