Find and fix memory leak

[commjoen]

after running hey twice against /challenge/1 we see that the amount of sessions build up to 400, and memory consumption goes from 200Mb to 277 MB after which, when all sessions are released, we still see 274 MB in use (e.g. 70 MB is not GCed?)

[commjoen]

Hi @drnow4u & @nbaars I am not sure if this is still an issue actually, but maybe we can tackle this with the config refactor?

[commjoen]

We have to check if this is still an issue in the current 1.8.0 or close it

[commjoen]

When we create 400 sessions in heroku, we see a rise from 313 mb to 320. When the sessions are expired, we go back to 316 mb. so there seems to be 3 megabyte leaking... this should not be a problem unless we play centralized CTFs on hosts with little ram, while folks doing all sorts of DAST testing in the hope to find secrets...