在ASM alert日志看到一段话
引用
Fri Mar 5 00:03:10 2010
Starting background process ASMB
ASMB started with pid=13, OS id=42068
Fri Mar 5 00:06:19 2010
NOTE: ASMB process exiting due to lack of ASM file activity
于是初步研究了一下该进程的作用，以下摘录来自
http://www.dbasupport.com/oracle/ora10g/ASM01.shtml
引用
Every database instance that uses ASM for file storage will also need two new processes. The Rebalancer background process (RBAL) handles global opens of all ASM disks in the ASM Disk Groups, while the ASM Bridge process (ASMB) connects as a foreground process into the ASM instance when the regular database instance starts. ASMB facilitates communication between the ASM instance and the regular database, including handling physical file changes like data file creation and deletion.
ASMB exchanges messages between both servers for statistics update and instance health validation. These two processes are automatically started by the database instance when a new Oracle file type – for example, a tablespace’s datafile — is created on an ASM disk group. When an ASM instance mounts a disk group, it registers the disk group and connect string with Group Services. The database instance knows the name of the disk group, and can therefore use it to locate connect information for the correct ASM instance.
附rdbms、asm instance的后台进程
引用
$ ps -ef|grep asmdb
oracle 7534 1 0 00:03:16 – 0:00 ora_rbal_asmdb
oracle 14186 1 0 00:44:53 – 0:00 ora_o000_asmdb
oracle 15268 1 0 00:03:12 – 0:00 ora_reco_asmdb
oracle 16016 1 0 00:03:12 – 0:02 ora_smon_asmdb
oracle 22202 1 0 00:03:12 – 0:01 ora_mmnl_asmdb
oracle 22492 1 0 00:03:12 – 0:03 ora_mmon_asmdb
oracle 23238 1 0 00:03:12 – 0:01 ora_ckpt_asmdb
oracle 26366 1 0 00:03:13 – 0:00 ora_s000_asmdb
oracle 26658 1 0 00:03:12 – 0:00 ora_d000_asmdb
oracle 30206 1 0 00:03:11 – 0:00 ora_dbw0_asmdb
oracle 30734 1 0 00:03:11 – 0:00 ora_mman_asmdb
oracle 35138 1 0 00:03:11 – 0:00 ora_psp0_asmdb
oracle 36398 1 0 00:03:36 – 0:00 ora_qmnc_asmdb
oracle 36646 1 0 00:03:11 – 0:00 ora_pmon_asmdb
oracle 38926 1 0 00:03:19 – 0:00 ora_o001_asmdb
oracle 40296 1 0 00:03:12 – 0:00 ora_lgwr_asmdb
oracle 41306 1 0 00:03:16 – 0:00 ora_asmb_asmdb
oracle 41814 1 0 00:03:12 – 0:05 ora_cjq0_asmdb
oracle 42628 21640 0 00:46:18 pts/2 0:00 grep asmdb
oracle 43624 1 0 00:03:46 – 0:00 ora_q001_asmdb
oracle 43864 1 0 00:03:46 – 0:00 ora_q000_asmdb
$ ps -ef|grep asm_
oracle 10868 1 0 23:47:53 – 0:00 asm_smon_+ASM
oracle 12690 1 0 23:47:53 – 0:00 asm_rbal_+ASM
oracle 15494 1 0 23:47:53 – 0:00 asm_dbw0_+ASM
oracle 17320 1 0 23:47:53 – 0:00 asm_gmon_+ASM
oracle 29354 1 0 23:47:52 – 0:00 asm_mman_+ASM
oracle 31422 1 0 23:47:52 – 0:00 asm_psp0_+ASM
oracle 31506 1 0 23:47:52 – 0:00 asm_pmon_+ASM
oracle 32776 1 0 23:47:53 – 0:00 asm_lgwr_+ASM
oracle 34576 1 0 23:47:53 – 0:00 asm_ckpt_+ASM
oracle 40514 1 0 00:03:10 – 0:00 asm_o000_+ASM
oracle 42630 21640 0 00:46:24 pts/2 0:00 grep asm_
以下简单介绍各个进程的作用
引用
ARBx These are the slave processes that do the rebalance activity (where x
is a number).
CKPT The CKPT process manages cross-instance calls (in RAC).
DBWR This process manages the SGA buffer cache in the ASM instance.
DBWR writes out dirty buffers (changed metadata buffers) from the ASM
buffer cache to disk.
GMON This process is responsible for managing the disk-level activities
(drop/offline) and advancing diskgroup compatibility.
KATE The Konductor or ASM Temporary Errands (KATE) process is used
to process disks online. This process runs in the ASM instance and is started
only when an offlined disk is onlined.
LGWR The LGWR process maintains the ASM Active Change Directory
(ACD) buffers from the ASM instance and flushes ACD change records to
disk.
MARK The Mark Allocation Unit (AU) for Resync Koordinator (MARK)
process coordinates the updates to the Staleness Registry when the disks go
offline. This process runs in the RDBMS instance and is started only when
disks go offline in ASM redundancy diskgroups.
PING The PING process measures network latency and has the same
functionality in RDBMS instances.
PMON This manages processes and process death in the ASM instance.
PSP0 This process spawner process is responsible for creating and
managing other Oracle processes.
PZ9x These processes are parallel slave processes (where x is a number),
used in fetching data on behalf of GV$ queries.
RBAL This opens all device files as part of discovery and coordinates the
rebalance activity.
SMON This process is the system monitor and also acts as a liaison to the
Cluster Synchronization Services (CSS) process (in Oracle Clusterware) for
node monitoring.
VKTM This process is used to maintain the fast timer and has the same functionality in the RDBMS instances.