Oracle Spatial doesn't scale well with concurrent connections

[ivanopicco]

Hi all, I perform some performance tests on mapserv (CGI and FASTCGI), using Oracle and SDE connections to retrieve a simple feature layer from the same oracle (SDO) table (the layer was registered on SDE). I use Microsoft Web Strees Tool (WAST) to make the concurrent getmap requests. As the results show (see attach), Oracle doesn't scale well with concurrent connections. Mapserv can serve 12 concurrent SDE connections, but only 3 from Oracle.

The web server has 2 Intel Xeon 3.40GHz and 2GB of RAM and Linux CentOS 4.5. The database server is a Sun-Fire-V210 with Solaris 9, it has 2 sparcv9 processor operates at 1002 MHz and 2GB of RAM.

This is an extract from my mapfile: LAYER

NAME "CTR-SDE" STATUS ON DEBUG ON DATA "ctr_sde.comuni,SHAPE" TYPE POLYGON CONNECTIONTYPE SDE CONNECTION "bubble,port:5153,esri_sde,ctr_sde,ctr_sde" PROCESSING "CLOSE_CONNECTION=DEFER" TEMPLATE "template.html" METADATA

"WMS_SRS" "EPSG:32632" "WMS_NAME" "Comuni_SDE" "WMS_TITLE" "Comuni_SDE" "WMS_ABSTRACT" "Comuni SDE"

END CLASS

STYLE

OUTLINECOLOR 0 0 0 ANTIALIAS TRUE

END

END

END

LAYER

NAME "CTR-SDO" STATUS ON DEBUG ON DATA "GEOMETRY FROM comuni USING UNIQUE OBJECTID SRID 82344 FILTER

VERSION 10G"

TYPE POLYGON CONNECTIONTYPE oraclespatial CONNECTION 'ctr_sdo/ctr_sdo@bubble:1522/OLYMPIA' PROCESSING "CLOSE_CONNECTION=DEFER" TEMPLATE "template.html" METADATA

"WMS_SRS" "EPSG:32632" "WMS_NAME" "Comuni_SDO" "WMS_TITLE" "Comuni_SDO" "WMS_ABSTRACT" "Comuni SDO"

END CLASS

STYLE

OUTLINECOLOR 0 0 0 ANTIALIAS TRUE

END

END

END

In attach you find an extract from debug log regarding a stress test with 16 concurrent connections.