On 2019-03-18 15:33:17 +0100, Thomas Güttler wrote: > I did some benchmarking and in my setup there was major > performance difference. > > I tested a ByteA column. > > If I used ascii data the tests took 52 seconds. > If I used random binary data the test took 250 seconds. > > binary data is (roughly) five times slower than ascii data? > > Is this a know fact, or is there something wrong with my benchmark? > > I used Python and psycopg2. I don't see this here (Debian 9, Python 3,5, psycopg2 2.7.6, PostgreSQL 9.5). I modified my bench-bytea script (https://github.com/hjp/blob-bench) to restrict the byte values to printable ASCII (32 .. 126). There was absolutely no difference, as the attached graph shows. hp -- _ | Peter J. Holzer | we build much bigger, better disasters now |_|_) | | because we have much more sophisticated | | | hjp@xxxxxx | management tools. __/ | http://www.hjp.at/ | -- Ross Anderson <https://www.edge.org/>
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