Re: Multiple Indexing, performance impact

Tried with 2048 also, it complete took away the strange steep after 7:

D is now 2048

1. A: 36 B: 32 C: 35 D: 31
2. A: 69 B: 53 C: 38 D: 38
3. A: 97 B: 79 C: 40 D: 40
4. A: 131 B: 98 C: 48 D: 43
5. A: 163 B: 124 C: 52 D: 49
6. A: 210 B: 146 C: 66 D: 50
7. A: 319 B: 233 C: 149 D: 58
8. A: 572 B: 438 C: 268 D: 65
9. A: 831 B: 655 C: 437 D: 76
10. A: 1219 B: 896 C: 583 D: 79

What is the program called that flushes the buffers every 30 seconds on a
linux 2.2.x system?

Daniel Åkerud

> > Holy ultra-violet-active macaronies :)
> >
> > First I changed it to 256, then I changed it to 1024.
> >
> > -B 128 is A
> > -B 256 is B
> > -B 1024 is C
> >
> > New multiple-index performance data):
> >
> > 1. A: 36 B: 32 C: 35
> > 2. A: 69 B: 53 C: 38
> > 3. A: 97 B: 79 C: 40
> > 4. A: 131 B: 98 C: 48
> > 5. A: 163 B: 124 C: 52
> > 6. A: 210 B: 146 C: 66
> > 7. A: 319 B: 233 C: 149
> > 8. A: 572 B: 438 C: 268
> > 9. A: 831 B: 655 C:
> > 10. A: 1219 B: 896 C:
> >
> > The last test hasn't finished yet, but THANKS! I know the reson now, at
> > least... i'll try
> > 2048 also.
>
> Strange that even at 1024 performance still drops off at 7. Seems it
> may be more than buffer thrashing.
>
>
> > -B equals --brutal-performance ? ;)
>
> See my performance article on techdocs.postgresql.org.
>
> --
> Bruce Momjian | http://candle.pha.pa.us
> pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 853-3000
> + If your life is a hard drive, | 830 Blythe Avenue
> + Christ can be your backup. | Drexel Hill, Pennsylvania 19026
>