From adf103a557740ac10e6e8102773c8ae879b45469 Mon Sep 17 00:00:00 2001 From: Konstantin Knizhnik Date: Tue, 22 Jul 2025 18:52:25 +0300 Subject: [PATCH] Update test_runner/performance/test_unlogged.py Co-authored-by: Heikki Linnakangas --- test_runner/performance/test_unlogged.py | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/test_runner/performance/test_unlogged.py b/test_runner/performance/test_unlogged.py index 2c39ddfea8..58815062c8 100644 --- a/test_runner/performance/test_unlogged.py +++ b/test_runner/performance/test_unlogged.py @@ -17,13 +17,13 @@ if TYPE_CHECKING: # Originally Neon always called `mdexists` to check if the local file exists and determine if it's an unlogged relation. Now we check the cache first. # mdexists is not so cheap: it closes and opens the file. # -# This test tries to emulate situation when most of writes are with persistence=0. -# We create multiple connections to the database and in each fill it's own table. So each backends writes only it's own table and other tables -# descriptors are not cached. At the same time all backends perform eviction from shared buffers. Probability that backends evicts page of it's own +# This test tries to recreate the situation that most of writes are with persistence=0. +# We open multiple connections to the database and in each fill its own table. So each backends writes only its own table and other table's +# descriptors are not cached. At the same time all backends perform eviction from shared buffers. Probability that backends evicts page of its own # relation is 1/N when N is number of relations=number of backends. The more relations, the smaller probability. # For large enough number of relations most of writes are with unknown persistence. # -# At Linux this test shows about 2x time speed improvement. +# On Linux, introducing the relpersistence cache shows about 2x time speed improvement in this test. # @pytest.mark.timeout(10000) def test_unlogged(neon_env_builder: NeonEnvBuilder):