Subject | High value of "Writes from cache to disk", why? |
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Author | juergen.modic |
Post date | 2013-08-17T04:21:05Z |
Hello,
I have created the db1 example database from IBExperts on two different systems.
At my local Linux machine the execution of INITALL(10.000) needs about 16 seconds on a Linux server it needs about 26 seconds.
The only significant different, except the execution time, in the performance info is the value of "Writes from cache to disk", with is about three times higher on the server system.
Linux Workstation:
------ Performance info ------
Prepare time = 0ms
Execute time = 15s 883ms
Current memory = 36.187.152
Max memory = 36.702.216
Memory buffers = 2.048
Reads from disk to cache = 143
Writes from cache to disk = 564
Fetches from cache = 3.579.797
Linux Server:
------ Performance info ------
Prepare time = 0ms
Execute time = 25s 797ms
Current memory = 36.190.992
Max memory = 36.714.840
Memory buffers = 2.048
Reads from disk to cache = 134
Writes from cache to disk = 1.516
Fetches from cache = 3.561.668
What can be the reason for the high number of cache writes to disk?
And how to change this behavior?
Any hints are welcome. Thanks in advance.
I have created the db1 example database from IBExperts on two different systems.
At my local Linux machine the execution of INITALL(10.000) needs about 16 seconds on a Linux server it needs about 26 seconds.
The only significant different, except the execution time, in the performance info is the value of "Writes from cache to disk", with is about three times higher on the server system.
Linux Workstation:
------ Performance info ------
Prepare time = 0ms
Execute time = 15s 883ms
Current memory = 36.187.152
Max memory = 36.702.216
Memory buffers = 2.048
Reads from disk to cache = 143
Writes from cache to disk = 564
Fetches from cache = 3.579.797
Linux Server:
------ Performance info ------
Prepare time = 0ms
Execute time = 25s 797ms
Current memory = 36.190.992
Max memory = 36.714.840
Memory buffers = 2.048
Reads from disk to cache = 134
Writes from cache to disk = 1.516
Fetches from cache = 3.561.668
What can be the reason for the high number of cache writes to disk?
And how to change this behavior?
Any hints are welcome. Thanks in advance.