Monitor statistics interpretation

[MPeccorini]

Hi fellows,

I'm somewhat confused about several statistics shown in the Pervasive Monitor.

First, what is the difference between clients, licenses in use and total remote connections. I don´t understand why this numbers are so different.

Second, it is recommended to have communications threads set to 32 if you have 32 clients (for example), if you have more clients you should analyze if it is reasonable to increase the number of threads. Can somebody explain me the situation given the following numbers:
CURRENT PEAK MAXIMUM
CLIENTS 35 48 10000
LICENSES 11 11 50
COMMS THREADS 0 5 16
REMOTE CONNS 20 39 100

I don´t know if I should follow the previous recommendation given that my COMMUNICATIONS THREADS PEAK is just 5.

Finally, is there a way to determine if my CACHE ALLOCATION SIZE is too low. I have found some ways to calculate the recommended but it is based on the size of the databases used. I think that aproach is not the best since not all files from a database are used at the same time. Isn´t there a way to calculate the CACHE HITS/CACHE MISSES ratio for example? or to determine a TOO MUCH I/O RATIO (I don´t know how)?

Thanks a lot for your help and best regards.

Mauricio Peccorini

BTW.: I'm using PSQL 2000i Server and PSQL 2000i WGE as client. The specific problem I'm trying to solve is that even very easy queries (like SELECT some_desc FROM some_catalog WHERE item_id = some_value) have a very high response time (1 or 2 seconds).

 

[TomKane]

I thin kthat the difference between clients and licences is that clients has to do with the number of connections (regardless of user) whereas number of licences has to do with the number of actual licenses being used (regardless of how many connections by a client)

 

[MPeccorini]

I think the same Tom, however, I would like to be sure about it.

Thanks a lot,

 

[TomKane]

I got this out of the manual:

Files
Indicates the number of active files.
Handles Indicates the number of active handles. The MicroKernel creates a handle each time a user opens a file; therefore, a single user can have several handles for the same file.

Clients
Indicates the number of clients accessing the MicroKernel. A workstation can have multiple clients accessing the engine simultaneously. You set the maximum for this field with the Configuration utility (see Active Clients ).
Worker Threads Indicates the number of concurrent MicroKernel processes.

Licenses in Use
Indicates the number of connected client licenses in use as defined by your licensing agreement. In this case, the maximum shows the number of users your licensing agreement allows.

Transactions
Indicates the number of transactions. The maximum for this field is unlimited.

Locks
Indicates the number of record locks. The maximum for this field is unlimited.

 

[MPeccorini]

Thanks a lot, it clarifies that issue. Do you know what should I do about the performance and the configuration settings I mention above?

 

[BtrieveBill]

SQL performance won't be attributed to these settings. Instead, it is more related to access times to the data required.

First, be sure that your WHERE clause is access an indexed field. More importantly, if the field is in a segmented index, it must be the FIRST field of the index (or first two fields, if you have two clauses connected with an AND) to be able to leverage the index. If needed, you can always add an index if this query is critical to you.

Second, be sure that the DDF's match the Btrieve files. Run the Check Database Wizard and do a full check of all tables. If the files report any consistency problems in this table, then you will likely have performance problems as well. Fix the DDF's (or tables) and it should work better.


Bill Bach
Goldstar Software Inc.

http://www.goldstarsoftware.com

 

[MPeccorini]

The application is a third party so I can't determine the quality of the WHERE clauses but I'm pretty sure they are OK. By the way, the application was previously installed using the Workgroup Engine and all the problems started when we changed the deployment to Server Engine.

The same consideration applies to DDF's quality.

Best regards,