Re: Higher Memory Usage with vsicurl and gdal > 2.2.4
I solved my problem... I found a way to reduce memory utilization and allocations when using MapServer with GDAL >= 2.3.0:
CONFIG "GDAL_HTTP_MULTIRANGE" "SERIAL"
With this setting, the memory footprint matches that of GDAL <= 2.2.4.
With the default (YES) has mapserv allocates much more memory. Running mapserv with supervisor & configured over FCGI results in a much higher memory footprint over time. My best guess is that with the default parallel mode has many HTTP connections kept alive and each connection consumes some non-trivial amount of memory. With CONFIG "CPL_CURL_VERBOSE" "ON", I see 9 HTTP connections kept around only with the default GDAL_HTTP_MULTIRANGE=ON setting: