rocksdb/e

ar: creating libmemenv.a
ar: creating libleveldb.a
Enhance db_bench Summary: Add --benchmarks=updaterandom for read-modify-write workloads. This is different from --benchmarks=readrandomwriterandom in a few ways. First, an "operation" is the combined time to do the read & write rather than treating them as two ops. Second, the same key is used for the read & write. Change RandomGenerator to support rows larger than 1M. That was using "assert" to fail and assert is compiled-away when -DNDEBUG is used. Add more options to db_bench --duration - sets the number of seconds for tests to run. When not set the operation count continues to be the limit. This is used by random operation tests. --use_snapshot - when set GetSnapshot() is called prior to each random read. This is to measure the overhead from using snapshots. --get_approx - when set GetApproximateSizes() is called prior to each random read. This is to measure the overhead for a query optimizer. Task ID: # Blame Rev: Test Plan: run db_bench Revert Plan: Database Impact: Memcache Impact: Other Notes: EImportant: - begin PUBLIC platform impact section - Bugzilla: # - end platform impact - Reviewers: dhruba Reviewed By: dhruba Differential Revision: https://reviews.facebook.net/D9267 12 years ago			`ar: creating libmemenv.a`
			`ar: creating libleveldb.a`