Database Reference
In-Depth Information
0:00:00.015 0:00:00.156 88 1049 1192 8 88 4 396 svchost.exe
0:00:00.109 0:00:04.640 744 1229 2432 8 81 3 460 cvpnd.exe
0:00:02.015 0:00:12.078 1476 17578 1904 13 139 3 600 VMwareService.exe
0:00:00.031 0:00:00.093 124 1004 1172 8 105 6 192 alg.exe
0:00:00.062 0:00:00.937 2648 13977 22656 8 101 3 720 TNSLSNR.EXE
0:04:00.359 0:02:57.734 164844 2009785 279168 8 550 29 1928 oracle.exe
0:00:00.093 0:00:00.437 6736 2316 2720 8 141 6 1224 msiexec.exe
0:00:00.015 0:00:00.031 2668 701 1992 8 34 1 804 cmd.exe
0:00:00.015 0:00:00.000 964 235 336 8 11 1 2856 pstat.exe
Here we can see there are 29 threads (
Thd
in the display) contained in the single Oracle process. These threads
represent what were processes on UNIX/Linux—they are the
pmon
,
arch
,
lgwr
, and so on. They each represent a
separate bit of the Oracle process. Paging down through the
pstat
report, we can see more details about each thread:
pid:788 pri: 8 Hnd: 550 Pf:2009785 Ws: 164844K oracle.exe
tid pri Ctx Swtch StrtAddr User Time Kernel Time State
498 9 651 7C810705 0:00:00.000 0:00:00.203 Wait:Executive
164 8 91 7C8106F9 0:00:00.000 0:00:00.000 Wait:UserRequest
...
a68 8 42 7C8106F9 0:00:00.000 0:00:00.031 Wait:UserRequest
We can't see the thread “names” like we could on UNIX/Linux (
ora_pmon_ora12c
and so on), but we can see the
thread IDs (
Tid
), priorities (
Pri
), and other operating system accounting information about them.
Connecting to Oracle
In this section, we'll take a look at the mechanics behind the two most common ways to have requests serviced by an
Oracle server:
dedicated server
and
shared server
connections. We'll see what happens on the client and the server in
order to establish connections, so we can log in and actually do work in the database. Lastly, we'll take a brief look at
how to establish TCP/IP connections; TCP/IP is the primary networking protocol used to connect over the network
to Oracle. And we'll look at how the listener process on our server, which is responsible for establishing the physical
connection to the server, works differently in the cases of dedicated and shared server connections.
Dedicated Server
Figure
2-1
and the following
ps
output present a picture of what an Oracle database named
ora12cr1
might look like
immediately after starting.
[tkyte@dellpe]$ ps -aef | grep _$ORACLE_SID
ora12cr1 19607 1 0 15:16 ? 00:00:00 ora_pmon_ora12cr1
ora12cr1 19609 1 0 15:16 ? 00:00:00 ora_psp0_ora12cr1
ora12cr1 19611 1 0 15:16 ? 00:00:00 ora_vktm_ora12cr1
ora12cr1 19615 1 0 15:16 ? 00:00:00 ora_gen0_ora12cr1
ora12cr1 19617 1 1 15:16 ? 00:00:00 ora_mman_ora12cr1
ora12cr1 19621 1 0 15:16 ? 00:00:00 ora_diag_ora12cr1
ora12cr1 19623 1 0 15:16 ? 00:00:00 ora_dbrm_ora12cr1
ora12cr1 19625 1 0 15:16 ? 00:00:00 ora_dia0_ora12cr1
ora12cr1 19627 1 0 15:16 ? 00:00:00 ora_dbw0_ora12cr1
ora12cr1 19629 1 0 15:16 ? 00:00:00 ora_lgwr_ora12cr1
ora12cr1 19631 1 0 15:16 ? 00:00:00 ora_ckpt_ora12cr1
