Runtime dependency from size of a bytea field

Hi,

We have done the following test with PostgreSQL 9.0.

create table bytea_demo ( index int, part1 bytea)");

Then we have instantiated a loop (1000) with the following action:

insert into bytea_demo ( index, part1, ) values ('%d', '%s');
", i, entry);

1a) In a first measurement part is supported with a bytea area (entry) of 4000 bytes (4000 characters)
1b) In a second run part is supported with a bytea area (entry) of 5000 bytes (5000 characters).

Result: The runtime of case 1a) is ~ 3 sec, however for case 1b) the runtime is ~ 43 sec. Why here we have such a large difference in runtime.

BR
Ingo Sander

Best Regards/mfG
Ingo Sander
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