原作者：范计杰
在ORACLE中ASH是非常有用的性能问题诊断工具，在Mogdb中是否有对象的功能呢？答案是有的，叫做ASP(ACTIVE SESSION PROFILE).虽然指标还比较粗，但总算是有了。
下面以ORACLE DBA的视角是探索一下ASP。
有哪些参数?
[omm2@og01 ~]$ gsql -c "show all"|grep asp
asp_flush_mode | table | Sets the active session profile flush mode:file/table/all.
asp_flush_rate | 10 | every Nth sample to disk, MOD(sample_id, N) = 0 will flush to dist
asp_log_directory | asp_data/test | Sets the destination directory for asp log files.
asp_log_filename | asp-%Y-%m-%d_%H%M%S.log | Sets the file name pattern for asp data files.
asp_retention_days | 2 | set max retention days for pg_asp
asp_sample_interval | 1s | Sets the active session profile max sample nums in buff
asp_sample_num | 100000 | Sets the active session profile max sample nums in buff
enable_asp | on | Enable active session profile
有哪些视图?
MogDB=# show search_path;
search_path
--------------------------
"$user", publi, dbe_perf
(1 row)
MogDB=# \dv *sess*
List of relations
Schema | Name | Type | Owner | Storage
------------+------------------------------+------+-------+---------
dbe_perf | global_session_memory | view | omm2 |
dbe_perf | global_session_memory_detail | view | omm2 |
dbe_perf | global_session_stat | view | omm2 |
dbe_perf | global_session_stat_activity | view | omm2 |
