Sybase Cache Test
This test reports the statistics pertaining to the default data cache and for all the named caches configured in a Sybase database server.
Target of the test : A Sybase ASE (Below v15) server
Agent deploying the test : An internal agent
Outputs of the test : One set of results for the default cache and every named cache being monitored.
Parameter | Description |
---|---|
Test Period |
How often should the test be executed. |
Host |
Refers to the IP address of the Sybase server. |
Port |
The port number at which the Sybase server listens to. |
User |
A Sybase user who has the “sa_role”. |
Password |
The password corresponding to the above user |
Confirm Password |
Confirm the password by retyping it here. |
Detailed Diagnosis |
To make diagnosis more efficient and accurate, the eG Enterprise embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the detailed diagnosis capability of this test for a particular server, choose the On option. To disable the capability, click on the Off option. The option to selectively enable/disable the detailed diagnosis capability will be available only if the following conditions are fulfilled:
|
Measurement | Description | Measurement Unit | Interpretation |
---|---|---|---|
Cache utilization |
The number of searches using this cache as a percentage of searches across all caches.
|
Percent |
Compare this value for each cache to determine if there are caches that are over or under-utilized. If you decide that a cache is not well utilized, you can
|
Cache hit ratio |
The percentage of times that a required page was found in the data cache. |
Percent |
A low value indicates that the cache may be too small for the current application load. |
Spinlock contention |
The number of times an engine encountered spinlock contention on the cache, and had to wait, as a percentage of the total spinlock requests for that cache. |
Percent |
If spinlock contention is more than 10%, consider using named caches or adding cache partitions. |
Buffers grabbed |
The average number of times that Adaptive Server fetched a buffer from the LRU end of the cache, replacing a database page. |
Buffers/Sec |
The detailed diagnosis of this measure, if enabled, reports the buffers grabbed for each configured memory pool. If this value is high in some pools and low in other pools, you might want to move space from the less active pool to the more active pool, especially if it can improve the cache-hit ratio. |
Dirty buffers grabbed |
The average number of times that fetching a buffer found a dirty page at the LRU end of the cache and had to wait while the buffer was written to disk. |
Buffers/Sec |
A nonzero value indicates that the wash area of the pool is too small for the throughput in the pool. The detailed diagnosis of this measure, if enabled, reports the dirty buffers grabbed for each configured memory pool. |
Large I/Os denied |
The number of large I/O requests denied as a percentage of the total number of requests made |
Percent |
Large I/O requests are denied due to the following reasons:
If a high percentage of large I/Os were denied, it indicates that the use of the large pools might not be as effective as it could be. |
Large I/O effectiveness |
The total number of pages that were used after being brought into cache by large I/O |
Percent |
A low value indicates that only few of the pages brought into cache are being accessed by queries. |