On 3/22/19 6:04 AM, Thomas Güttler wrote:
Am 22.03.19 um 13:40 schrieb Francisco Olarte:
Thomas:
On Fri, Mar 22, 2019 at 11:22 AM Thomas Güttler
<guettliml@xxxxxxxxxxxxxxxxxx> wrote:
Thank you for asking several times for a benchmark.
I wrote it now and it is visible: inserting random bytes into bytea
is much slower,
if you use the psycopg2 defaults.
Here is the chart:
https://github.com/guettli/misc/blob/master/bench-bytea-inserts-postrgres.png
And here is the script which creates the chart:
https://github.com/guettli/misc/blob/master/bench-bytea-inserts-postrgres.py
I'm not too sure, but I read ( in the code ) you are measuring a
nearly not compressible urandom data againtst a highly compressible (
'x'*i ) data,
are you sure the difference is not due to data being compressed and
generating much less disk usage in toast-tables/wal?
+1
for this case toast-tables/wal is a detail of the implementation.
This tests does not care about the "why it takes longer". It just generates
a performance chart.
TOAST is tunable, might want to take a look at:
https://www.postgresql.org/docs/11/storage-toast.html
Yes, it does exactly what you say: it compares
nearly not compressible urandom data against a highly compressible data.
In my case, will get nearly random data (binary PDF, JPG, ...). And
that's why
I wanted to benchmark it.
Regards,
Thomas
--
Adrian Klaver
adrian.klaver@xxxxxxxxxxx
