Estimate a reasonable cache size if one isn't provided in app/env config for wterl. #5

Merged

gburd merged 1 commit from gsb-cache-size-est into master

2013-03-14 18:05:38 +00:00

Author	SHA1	Message	Date
Gregory Burd	1d6dfee192	Cache sizing is critical for performance. This change guesses at a reasonable setting for the WiredTiger cache size at runtime. This cache is shared across all vnodes regarless of how many are active at any given time. The algorithm is: max(1GB, 1/3 (RAM - Beam RSS size)). We don't enable direct_io on purpose and data will be double buffered in WiredTiger's cache and the filesystem buffer cache. This turns out to be faster than direct I/O despite wasting a bit of RAM.	2013-03-14 13:27:59 -04:00

Author

SHA1

Message

Date

Gregory Burd

1d6dfee192

Cache sizing is critical for performance. This change guesses at a

reasonable setting for the WiredTiger cache size at runtime.  This cache
is shared across all vnodes regarless of how many are active at any
given time.  The algorithm is: max(1GB, 1/3 (RAM - Beam RSS size)). We don't
enable direct_io on purpose and data will be double buffered in WiredTiger's
cache and the filesystem buffer cache.  This turns out to be faster than
direct I/O despite wasting a bit of RAM.

2013-03-14 13:27:59 -04:00