| Subject | Re: firebird 3.0 ten times slower than 2.5 ? |
|---|---|
| Author | |
| Post date | 2017-03-09T08:29:49Z |
---In firebird-support@yahoogroups.com, <michkurc@...> wrote :
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Reads = 37865
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...
...
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It is strange that FB3 reads 2 times more than FB2.5. You show that page size is the same in
both databases (16KB). What about charset of varchar field ? gstat -r also could be useful to see.
Regards,
Vlad
is still difference between 2.5 and 3.0:for select first 1000000 *> In my box in isql mode ( win7_x64, dedicated ssd drive for databases)
> default db configuration
>
>
>(now over 100% of time fb 2.5)
>//2.5
>
>
>SQL> select count(*) from t1;
...
> Elapsed time= 4.44 secBuffers = 2048
Reads = 37865
...
>SQL> select first 1000000 * from t1 order by id desc;
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> Elapsed time= 22.34 secBuffers = 2048
>
>Reads = 37869
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>// 3.0
...
> Elapsed time= 5.143 secBuffers = 2048
>
>Reads = 80764
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> SQL> select first 1000000 * from t1 order by id desc;...
> Elapsed time= 55.905 secBuffers = 2048
>
>Reads = 80701
It is strange that FB3 reads 2 times more than FB2.5. You show that page size is the same in
both databases (16KB). What about charset of varchar field ? gstat -r also could be useful to see.
Regards,
Vlad