On Mon, 2 Sept 2024 at 10:12, Amit Kapila <amit.kapil...@gmail.com> wrote: > > On Fri, Aug 30, 2024 at 3:06 PM Shlok Kyal <shlok.kyal....@gmail.com> wrote: > > > > Next I am planning to test solely on the logical decoding side and > > will share the results. > > > > Thanks, the next set of proposed tests makes sense to me. It will also > be useful to generate some worst-case scenarios where the number of > invalidations is more to see the distribution cost in such cases. For > example, Truncate/Drop a table with 100 or 1000 partitions. > > -- > With Regards, > Amit Kapila.
Also, I did testing with a table with partitions. To test for the scenario where the number of invalidations are more than distribution. Following is the test case: 1. Created a publisher on a single table, say 'tconc_1'; 2. Created a second publisher on a partition table say 'tp'; 3. Created 'tcount' partitions for the table 'tp'. 4. two sessions are running in parallel, let's say S1 and S2. 5. Begin a transaction in S1. 6. S1: Insert a row in table 'tconc_1' S2: BEGIN; TRUNCATE TABLE tp; COMMIT; With patch, this will add 'tcount * 3' invalidation messages to transaction in session 1. S1: Insert a row in table 't_conc1' 7. COMMIT the transaction in S1. 8. run 'pg_logical_slot_get_binary_changes' to get the decoding changes. Performance: We see a degradation in performance. Results are an average of 5 runs. count of partitions | Head (sec) | Fix (sec) | Degradation (%) ------------------------------------------------------------------------------------- 1000 | 0.114 | 0.118 | 3.50877193 5000 | 0.502 | 0.522 | 3.984063745 10000 | 1.012 | 1.024 | 1.185770751 I have also attached the test script here. And will also do further testing. Thanks and Regards, Shlok Kyal
test3.pl
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