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8 lines
539 B
SQL
8 lines
539 B
SQL
SELECT sum(cityHash64(*)) FROM test.hits SETTINGS max_threads=40;
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-- We had a bug which lead to additional compressed data read. test.hits compressed size is about 1.2Gb, but we read more then 3Gb.
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-- Small additional reads still possible, so we compare with about 1.5Gb.
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SYSTEM FLUSH LOGS;
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SELECT ProfileEvents['ReadBufferFromFileDescriptorReadBytes'] < 1500000000 from system.query_log where query = 'SELECT sum(cityHash64(*)) FROM test.hits SETTINGS max_threads=40;' and current_database = currentDatabase() and type = 'QueryFinish';
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