Identify in details the consumption of memory from a specific session

Identify in details the consumption of memory from a specific session

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We are using Oracle 11g standard, without any options (diag/tunning/perf). I can identify one session with the SQL bellow which having a high consumption (1.4 GB) of memory on the past hours... (pga and uga) There is someway to get details about this consumption? If is the use of temporary tables or something else? with x as (select s.osuser osuser , s.username , s.status , se.sid , s.serial# serial , n.name , round(max(se.value)/1024/1024, 2) maxmem_mb , max(se.value) as maxmem from v$sesstat se , v$statname n , v$session s where n.statistic# = se.statistic# and n.name in ('session pga memory','session pga memory max', 'session uga memory','session uga memory max') and s.sid = se.sid group by s.osuser, s.username, s.status, se.sid, s.serial#, n.name order by maxmem desc ) select * from x where rownum < 5 ; oracle share improve this question asked Mar 18 at 18:47 ceinmart 203 1 9

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You could check which statement is executed and what it does. Way to go is to get SQL_ID from v$session and join it with v$sqlstats. You can use DBMS_XPLAN to check the execution plan of your statement. With this information you have some hints which buffers are used. Another possibility is to install perfstat, take a snapshot, start your session, and take another snapshot when your session is done. The perfstat output gives quite a detailed picture of the database activity. share improve this answer answered Mar 18 at 19:55 jmk 39 3

Is perfstat paid? –  ceinmart Mar 20 at 17:30 1   No, perfstat/statspck is distributed with the database, you don't need any additional licencse. For AWR reports you need the diagnoctic pack. –  jmk Mar 20 at 17:33 ok, I sad because I don't found any clear SQL to identify something which appear be basic... anyway... I will try the perfstats , if works I accept the answer. thanks! –  ceinmart Mar 21 at 0:44 add a comment

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After some research I've discovered the view V$PROCESS_MEMORY_DETAIL and how use it. By default it's always empty and need some commands to "enable" it (oradebug or alter session). References I found: How To Find Where The Memory Is Growing For A Process (Doc ID 822527.1) Oracle Memory Troubleshooting, Part 4: Drilling down into PGA memory usage with V$PROCESS_MEMORY_DETAIL This quote from Oracle Article says everything : How to use V$PROCESS_MEMORY and V$PROCESS_MEMORY_DETAIL to identify where the memory is growing. In Oracle 10.2 and higher exist 2 new views that can be used to find where the memory continue to grow. This views can be used instead of heap dump to find where the memory is growing: - V$PROCESS_MEMORY: This view displays dynamic PGA memory usage by named component categories for each Oracle process. This view will contain up to six rows for each Oracle process, one row for: - Java - PL/SQL - OLAP - SQL - Freeable - Other - V$PROCESS_MEMORY_DETAIL Contain break down of memory allocation for each component. - To activate this view can one of following commands executed: SQL> alter session set events'immediate trace name PGA_DETAIL_GET level <PID>'; From ORADEBUG: SQL> ORADEBUG SETMYPID; SQL> ORADEBUG DUMP PGA_DETAIL_GET <PID>; - To remove all rows in the view run following command: SQL> alter session set events'immediate trace name PGA_DETAIL_CANCEL level <PID>'; From ORADEBUG: SQL> ORADEBUG DUMP PGA_DETAIL_CANCEL <PID>; and a useful SQL: SELECT s.sid,p.spid,pm.* FROM v$session s , v$process p , v$process_memory pm WHERE s.paddr = p.addr AND p.pid = pm.pid -- AND p.spid IN (1423) AND s.sid IN (244) ORDER BY sid , category Here is the informations detailed... Just needs digging the mysterious names . 1* select * from v$process_memory_detail SQL> / PID SERIAL# CATEGORY NAME HEAP_NAME BYTES ALLOCATION_COUNT HEAP_DESCRIPTOR PARENT_HEAP_DESC ---------- ---------- --------------- -------------------------- --------------- ---------- ---------------- ---------------- ---------------- 15 1 SQL miscellaneous 18880 80 00 00 15 1 Other koi korfc koh-kghu sessi 24544 2 0000002A97A1A1C0 0000002A97935BE0 15 1 Other kxsFrame8kPage session heap 24744 3 0000002A97935BE0 000000000B0BC680 15 1 PL/SQL static frame of inst koh-kghu sessi 26696 3 0000002A97A2BD50 0000002A97935BE0 15 1 Other kgsc ht segs session heap 29824 327 0000002A97935BE0 000000000B0BC680 15 1 Other kgh stack pga heap 32832 1 000000000B0B6C20 00 15 1 Other kopo object koh-kghu sessi 34728 3 0000002A97A1A1C0 0000002A97935BE0 15 1 Other koh-kghu session heap session heap 35352 15 0000002A97935BE0 000000000B0BC680 15 1 Other Fixed Uga pga heap 39024 1 000000000B0B6C20 00 15 1 PL/SQL miscellaneous 64736 47 00 00 15 1 Other mark Alloc server h 101088 24 0000002A97A99ED0 0000002A9795E090 15 1 Other free memory top call heap 107520 3 000000000B0BC460 00 15 1 Other mark Alloc environm 111576 18 0000002A9795E090 0000002A97935BE0 15 1 Other kxsFrame4kPage session heap 120408 29 0000002A97935BE0 000000000B0BC680 15 1 Other free memory session heap 345672 213 0000002A97935BE0 000000000B0BC680 15 1 Other miscellaneous 380264 619 00 00 15 1 Other free memory pga heap 917616 4618 000000000B0B6C20 00 15 1 Other permanent memory koh-kghu call 2618480 32731 0000002AAE10E8C0 000000000B0B6C20 15 1 Other permanent memory koh dur heap d 2619072 32731 0000002A97947E40 0000002A97935BE0 15 1 Other permanent memory session heap 7450512 180 0000002A97935BE0 000000000B0BC680 15 1 Other permanent memory pga heap 23983776 2907 000000000B0B6C20 00 15 1 Other kol vstring koh-kghu call 34298216 32727 0000002AAE10E8C0 000000000B0B6C20 15 1 Other kadaih image koh dur heap d 132475264 65452 0000002AAE0E66C8 000000000B0B6C20 15 1 Other koh-kghu call heap pga heap 164949272 65457 000000000B0B6C20 00 37 67 Other mark Alloc server h 8480 3 0000002A97870860 0000002A978715C8 37 67 Other KFKPGA KFK_IO_SUBHEAP 9936 1 0000002A97899E10 000000000B0B6C20 37 67 Other dbgr entry diag pga 12248 218 0000002A976007E0 000000000B0B6C20 37 67 Other permanent memory diag pga 16056 6 0000002A976007E0 000000000B0B6C20 37 67 PL/SQL miscellaneous 16232 34 00 00 37 67 PL/SQL PL/SQL STACK PLS PGA hp 16432 2 0000002A9788F150 000000000B0B6C20 37 67 Other kgh stack pga heap 17024 1 000000000B0B6C20 00 37 67 Other dbgeInitProcessCtx:InvCtx diag pga 17088 2 0000002A976007E0 000000000B0B6C20 37 67 Other kgsc ht segs session heap 17320 286 0000002A979467C8 000000000B0BC680 37 67 Other kxsc: kkspsc0 2 session heap 20056 23 0000002A979467C8 000000000B0BC680 37 67 Other koh-kghu session heap session heap 22752 10 0000002A979467C8 000000000B0BC680 37 67 Other free memory top uga heap 31880 1 000000000B0BC680 00 37 67 SQL miscellaneous 32728 93 00 00 37 67 Other kxsFrame16kPage session heap 32880 2 0000002A979467C8 000000000B0BC680 37 67 Other Fixed Uga pga heap 39024 1 000000000B0B6C20 00 37 67 Other free memory pga heap 47192 5 000000000B0B6C20 00 37 67 PL/SQL recursive addr reg file koh-kghu sessi 51112 3 0000002A9810AA50 0000002A979467C8 37 67 Other permanent memory session heap 52672 8 0000002A979467C8 000000000B0BC680 37 67 Other free memory session heap 72944 23 0000002A979467C8 000000000B0BC680 37 67 Other miscellaneous 101120 178 00 00 37 67 Other free memory top call heap 127936 3 000000000B0BC460 00 37 67 Other permanent memory pga heap 175960 22 000000000B0B6C20 00 37 67 Other kxsFrame4kPage session heap 195144 47 0000002A979467C8 000000000B0BC680 47 rows selected. share improve this answer edited Mar 28 at 20:14 answered Mar 28 at 20:03 ceinmart 203 1 9

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