logevent_max_q_sz
| Description | Maximum number of system
events allowed to be queued waiting for delivery to the syseventd daemon. Once the size of the system event queue reaches this limit,
no other system events will be allowed on the queue.
|
| Data Type | Integer
|
| Default | 2000
|
| Range | 0 to MAXINT
|
| Units | System events
|
| Dynamic? | Yes
|
| Validation | The sysevent framework
checks this value every time a system event is generated by ddi_log_sysevent(9F)
and sysevent_post_event(3SYSEVENT).
|
| When to Change | When error log messages
indicate that a system event failed to be logged, generated, or posted.
|
| Commitment Level | Unstable
|
fsflush and Related Tunables
This section describes fsflush and related tunables.
fsflush
The system daemon, fsflush, runs periodically to
do three main tasks:
Frequency of invocation, whether the memory scanning is executed, whether
the file system data flushing occurs, and the frequency with which it will
occur are configurable.
For most systems, memory scanning and file system metadata syncing are
the dominant activities for fsflush. Depending on system
usage, memory scanning can be of little use or consume too much CPU time.
tune_t_fsflushr
| Description | Specifies the number
of seconds between fsflush invocations.
|
| Data Type | Signed integer
|
| Default | 5
|
| Range | 1 to MAXINT
|
| Units | Seconds
|
| Dynamic? | No
|
| Validation | If the value is less
than or equal to zero, the value is reset to 5 and a warning message is displayed.
This check is only done at boot time.
|
| When to Change | See autoup below.
|
| Commitment Level | Unstable
|
autoup
| Description | Along with tune_t_flushr, autoup controls the amount of
memory examined for dirty pages in each invocation and frequency of file system
sync operations.
The value of autoup is also used to control whether
a buffer is written out from the free list. Buffers marked with the B_DELWRI flag (file content pages that have changed) are written
out whenever the buffer has been on the list for longer than autoup seconds. Increasing the value of autoup
keeps the buffers around for a longer time in memory.
|
| Data Type | Signed integer
|
| Default | 30
|
| Range | 1 to MAXINT
|
| Units | Seconds
|
| Dynamic? | No
|
| Validation | If autoup
is less than or equal to zero, it is reset to 30 and a warning message is
displayed. This check is only done at boot time.
|
| Implicit | autoup
should be an integer multiple of tune_t_fsflushr. At a
minimum, autoup should be at least 6 times tune_t_fsflushr. If not, excessive amounts of memory will be scanned each time fsflush is invoked.
(total system pages x tune_t_fsflushr) should be
greater than or equal to autoup to cause memory to be checked
if dopageflush is non-zero.
|
| When to Change | There are several
potential situations for changing autoup and or tune_t_fsflushr:
Systems with large amounts of memory--In this case, increasing autoup reduces the amount of memory scanned in each invocation
of fsflush.
Systems with minimal memory demand--Increasing both autoup
and tune_t_fsflushr reduces the number of scans made. autoup should be increased also to maintain the current ratio of autoup / tune_t_fsflushr.
Systems with large numbers of transient files (for example,
mail servers or software build machines)--If large numbers of files are
created and then deleted, fsflush might unnecessarily write
data pages for those files to disk.
|
| Commitment Level | Unstable
|
