Technical data

Using BACKUP
11.7 Setting Process Quotas for Efficient Backups
$ SET DEFAULT SYS$SYSTEM
$ RUN AUTHORIZE
UAF> SHOW SYSTEM
3. Using the System Management utility (SYSMAN), determine the value of the
system parameters WSMAX and CHANNELCNT, as follows:
$ RUN SYS$SYSTEM:SYSMAN
SYSMAN> PARAMETERS SHOW WSMAX
%SYSMAN-I-USEACTNOD, a USE ACTIVE has been defaulted on node DIEM
Node DIEM: Parameters in use: ACTIVE
Parameter Name Current Default Minimum Maximum Unit Dynamic
-------------- ------- ------- ------- ------- ---- -------
WSMAX 2600 1024 60 100000 Pages
SYSMAN> PARAMETERS SHOW CHANNELCNT
Parameter Name Current Default Minimum Maximum Unit Dynamic
-------------- ------- ------- ------- ------- ---- -------
CHANNELCNT 127 127 21 2047 Channels
SYSMAN> EXIT
$
In this case, the values for WSMAX and CHANNELCNT, as shown in the
column marked Current, are 2600 and 127, respectively. Use these values to
help set the correct values for the process quotas.
4. Use AUTHORIZE to compare the values for the process quotas to the
recommended values for efficient backups, as shown in Table 11–4.
Table 11–4 Recommended Process Quotas for Efficient Backups
Process Quota Recommended Setting
WSQUOTA Equal to system parameter WSMAX
WSEXTENT Equal to WSQUOTA quota
PGFLQUOTA Equal to or greater than WSEXTENT quota
FILLM Less than system parameter CHANNELCNT
DIOLM Either 4096 or three times the value of FILLM quota,
whichever is greater
ASTLM Either 4096, at least 100 greater than DIOLM quota, or three
times the value of FILLM quota, whichever is greater
BIOLM Equal to FILLM
BYTLM Equal to or greater than the following value:
ENQLM Greater than FILLM quota
5. If necessary, change process quotas using the AUTHORIZE command
MODIFY. If you change process quotas, you must log out and log in again
for the changes to take effect. For information about changing these process
quotas, see Section 7.7.2.
Table 11–5 lists a set of process quota values that are appropriate for many
configurations. If your disks are highly fragmented or if your backups will be
performed during periods of heavy system use, you should reduce the values
shown for WSQUOTA and FILLM.
Using BACKUP 11–11