Hi,
On 2013-06-18 11:35:10 +0200, Andres Freund wrote:
> Going to do some performance tests now.
Ok, so ran the worst case load I could think of and didn't notice
any relevant performance changes.
The test I ran was:
CREATE TABLE test_toast(id serial primary key, data text);
ALTER TABLE test_toast ALTER COLUMN data SET STORAGE external;
INSERT INTO test_toast(data) SELECT repeat('a', 8000) FROM generate_series(1, 200000);
VACUUM FREEZE test_toast;
And then with that:
\setrandom id 1 200000
SELECT id, substring(data, 1, 10) FROM test_toast WHERE id = :id;
Which should really stress the potentially added overhead since we're
doing many toast accesses, but always only fetch one chunk.
One other thing: Your latest patch forgot to adjust rules.out, so make
check didn't pass...
Greetings,
Andres Freund
-- Andres Freund http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
Services
