Oracle Tidbits – October 2015 #oratidbit


“ Oracle *daily* TidBits” (#oratidbit) published at on weekdaysin October2015. There were no tidbits during the week of OOW15. You will also see these tidbits, one tidbit at a time, for each page refresh on the right side of this blog as well… Hope you find these helpful to learn something new or to remind you of its existence and use…

TidBit #oratidbit ARSn (ASM Recovery Slave) processes (new in 12c) are spawned by ASM RBAL process to recover aborted ASM transactional operations. ARSn runs only on ASM instance. #oratidbit TMON process is new in #DB12c for Oracle Data Guard. TMON monitors the redo transport processes for hangs and death. #oratidbit CTWR (change tracking writer) process tracks changed data blocks as part of the Recovery Manager block change tracking feature. #oratidbit ASM Disk Scrubbing Master Process SCRB is new in #DB12c. SCRB runs in an Oracle ASM instance and coordinates Oracle ASM disk scrubbing operations. Related processes are ASM Disk Scrubbing Slave Check Process (SCCn), ASM Disk Scrubbing Slave Repair Process (SCRn), ASM Disk Scrubbing Slave Verify Process (SCVN) #oratidbit SGA Allocator process SAnn is new in #DB12c. A small fraction of SGA is allocated during instance startup. The SAnn process allocates the rest of SGA in small chunks. The process exits upon completion of SGA allocation. #oratidbit ASM Recovery Slave Process ARSn is new in #DB12c. The ASM RBAL background process coordinates and spawns one or more of these slave processes to recover aborted ASM transactional operations. These processes run only in the Oracle ASM instance. #oratidbit Manageability Monitor Process MMON in #DB12c collects statistics for the Automatic Workload Repository. MMON is started when the database instance starts. #oratidbit Rolling Migration Monitor Process RMON is new in #DB12c. RMON manages the rolling migration procedure for an Oracle ASM cluster (The RMON process is spawned on demand to run the protocol for transitioning an ASM cluster in and out of rolling migration mode) #oratidbit RAT Masking Slave Process is new in #DB12c. This background process is used with Data Masking and Real Application Testing. #oratidbit Log Writer Slave process LGn is new in #DB12c. On multiprocessor systems, LGWR creates slave processes to improve the performance of writing to the redo log. LGWR slaves are not used when there is a SYNC standby destination. #oratidbit Listener Registration Process LREG is new in #DB12c. LREG notifies the listeners about instances, services, handlers, and endpoint. In earlier releases, PMON had this responsibility. #oratidbit Space Management Coordinator Process SMCO in #DB12c coordinates the execution of various space management related tasks, such as proactive space allocation and space reclamation. SMCO is started when the database instance starts. #oratidbit Using the “crsctl replace votedisk” command, you can move a given set of RAC voting disks from one Oracle ASM disk group into another, or onto a certified file system.