On Thu, Jan 20, 2022 at 10:31:15PM +0000, Lugosi, Jim wrote: > We are struggling to figure out what is going on. We are migrating from > PostgreSQL 9.6 to PostgreSQL 13 w/ PostGIS. Our 9.6 version was compiled > from source and the new version (13) was installed using Yum. BTW, the new > version is on a VM that has 16GB of memory, two cores, and 500 GB of disk. > In addition, we are using MapServer as our mapping engine and OpenLayers as > the client side interface. Once we switch over to the new version of > PostgreSQL, the performance takes a big nose dive. We have being tweaking > and tuning the database and it appears to be happy but the response times > from mapfile requests are 3 -7 seconds. Previously, the response time was > below a second. > > Another point is that we populated the new database from the old (9.6), using > pg_dump. Could this be causing issues? Should we load the data from > scratch? We use ogr2ogr (GDAL) to help assist with loading of spatial data. > Anyway, not really sure what the problem is. > > Lastly, why am I seeing so many requests as to the PostGIS version. It > appears that every map request sends the following query "SELECT > PostGIS_Version();", which in turn takes up a connection.
This list is for postgres development and bug reports. I suggest to post here, instead: https://www.postgresql.org/list/pgsql-performance/ Here's a list of needed info: https://wiki.postgresql.org/wiki/Slow_Query_Questions It's important to include the slow query itself. -- Justin
