Björn,
> Executing a query with a little bit longer execution time I get negative
> numbers for some values. Execution is done via IBExpert. Firebird ist 2.5.1
> CS on Linux 64 bit Client Lib is 2.5.1 Windows 32 bit.
>
> Prepare time = 63ms
> Execute time = 43h 53m 31s 63ms
> Avg fetch time = 158.011.063,00 ms
> Current memory = -507.368.239
> Max memory = -466.997.327
> Memory buffers = 20.480
> Reads from disk to cache = 13.786.623
> Writes from cache to disk = 290.317
> Fetches from cache = -1.256.613.653
>
>
> Is it a bug in IBExpert or does the overflow occur in Firebird itself?
It is very likely that the engine/performance counter variables are SINT's, so
they are overflowing/wrapping.
Although, I have never personally understood what the memory variables
represent, I wouldn't be surprised if the values were in bytes, not KB, so a
query on a 64 bit server could easily use much more memory than the counter
variable could store/represent.
Sean
P.S. A 43 hour query is impressive!!! (a _bit_ longer)!!! I'm not sure if
that means that the query is running that long because of the amount of data/or
the nature of the query, or if the query could be optimized. {That is the type
of problem that I love to get my teeth into}
P.P.S. Have you tried to increase your db cache size to see if the number of
"reads from disk" would go down? (the current ratio of 100 "fetches from
cache" per "read from disk" is very good, but I wonder if it could be better --
I would hate to think of what the query performance would be like if you only
had a cache size of 2048)
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