10 most recommended metrics

The 10 most recommended metrics are taken from the V$SYSSTAT table:
*EB0rv;v%F*M051Testing软件测试网a
W+l i?,M
•        CPU used by this session - This is the amount of CPU time (in 10s of milliseconds) used by a session between when a user call started and ended. Some user calls can complete within 10 milliseconds and as a result, the start and end user-call time can be the same. In this case, 0 milliseconds are added to the statistic. A similar problem can exist in the reporting by the operating system, especially on systems that suffer from many context switches.
${W7u|\9c$dCxw3c0
T5u{j+W
v|D0•        Bytes received via SQL*Net from client - The total number of bytes received from the client over Net8.
-j\!G0`]Dp'E$I051Testing软件测试网 n5eV;XB6Z
•        Logons current - The total number of current logons. This statistic is useful only in V$SYSSTAT.51Testing软件测试网'~)w"T`Nu hR9ok
51Testing软件测试网+\8_!d"M hf
•        Opens of replaced files - The total number of files that needed to be reopened because they were no longer in the process file cache.
,{HD CQ8` b7mF0
,B g
ZBZMU s!o4c0•        User calls - Oracle allocates resources (Call State Objects) to keep track of relevant user call data structures every time you log in, parse, or execute. When determining activity, the ratio of user calls to RPI calls, give you an indication of how much internal work gets generated as a result of the type of requests the user is sending to Oracle.51Testing软件测试网qZN,Uv8Ua
51Testing软件测试网.Z#`vv t)n
•        SQL*Net roundtrips to/from client - Total number of Net8 messages sent to and received from the client.
s[%}8AmM#_+T'l0
$@-CX5C\'Mk@-] B0•        Bytes sent via SQL*Net to client - The total number of bytes sent to the client from the foreground process(es).
3Eo?l n6_5L%n0
,a'W4?3K4es0•        Opened cursors current - The total number of current open cursors.51Testing软件测试网-S2d+I9^jG
51Testing软件测试网
Z:uB Md
•        DB block changes - Closely related to consistent changes, this statistics counts the total number of changes that were made to all blocks in the SGA that were part of an update or delete operation. These are changes that are generating redo log entries and hence will be permanent changes to the database if the transaction is committed. This statistic is a rough indication of total database work. This statistic indicates (possibly on a per-transaction level) the rate at which buffers are being dirtied.51Testing软件测试网;N~M?!Hu;Y9[$W-KA'H C
•        Total file opens - The total number of file opens being performed by the instance. Each process needs a number of files (control file, log file, database file) in order to work against the database.