Table of Contents
Environment Variables
You'll rarely need to define environment variables. Don't do it unless you really need them.
Berkeley DB databases
These environment variables allows some specific tuning on BerkeleyDB databases environment. Usually, you won't need to define or use these variables, and you shall not do, unless you've previously read and understood how they work. Check Berkeley DB documentation.
- Database
DB_DB_CACHE_SIZE
- Environment
DB_ENV_CACHE_SIZE
DB_LK_MAX_LOCKS
DB_LK_MAX_OBJECTS
DB_LK_MAX_LOCKERS
- When the value of these variables are changed, the new environment may be incompatible with the old one. In this case, you shall stop the filter and remove database enviroment files (
__db.*
andlog.*
).
- Instead of defining these environment variable, you can use the usual
DB_CONFIG
file. Read more on BerkeleyDB documentation. If you want to experiment withDB_CONFIG
, a starting one can be :
set_cachesize 0 100000000 1 set_lk_max_locks 32768 set_lk_max_objects 32768
Content filter
ORDER_CHECKS
- this environment variable defines the order at which content checks are done, separated by commas. Defaut value is XFILES,VIRUS,CONTENT.
Greylisting
Cleaning up databases
Cleaning up greylisting databases (expire, validate, …) is done by a background task which runs, at least, each 10 minutes, as defined by GREY_CLEANUP_INTERVAL
configuration option. When this task runs, greylisting databases are locked. On really busy servers, it may be useful to tune these two parameters :
GREY_CLEANUP_SUB_INTERVAL
- default value :120 : 2 minutes
GREY_CLEANUP_DT_LOCK_MAX
- default value :1000 : 1 sec
GREYD_RECV_TIMEOUT
- default value : '2000 : 2 secs''