This topic helps you determine the calculate the number of file operations per second.
For various application types, the following table provides mapping between application transaction rate (APPOP) and file operations (FOP), that is, the number of expected file operations for each application transaction, and file operations (FOP) to metadata server operation (the number of expected metadata server operations for each file operation). The values in this table are based upon IBM internal testing and estimates based upon those test results.
Application type | Typical metric | Average FOP/APPOP | Average metadata server OP/FOP |
---|---|---|---|
Mail server | Mails per second | 20 | 3% |
Oltp database back end | Transactions per second | 2 | 5% |
Data Warehouse database back end | Tuples per second | 0.1 | 10% |
Office workgroup | Documents per second | 10 | 1% |
Web server | Connections per second | 5 | 10% |
Web proxy | Pages per second | 15 | 10% |
Peer-to-peer | Files per second | 12 | 10% |
Network File System Serving | Megabytes per second | 30 | 10% |
Common Internet File System Serving | Megabytes per second | 30 | 10% |
Compile Build (Development) | Files built per second | 10 | 5% |
User Folder Serving | Files used per second | 5 | 3% |
This table can be used to help estimate the rate of Metadata server operations generated by your application, given your application’s transaction serving rate. For example, if you have a mail server and you expect to serve 50 mails per second, the expected number of Metadata server operations generated would be 30.
After the number of metadata server operations is determined for your application, adjust the estimate using the previous table and answers to the application and environment questionnaire. Use the adjustment factors in the following table, as applicable.
Adjustment factor | |
Average file size larger than 500 Mb | + 20% |
File hotset > 10K | + 20% for each 10K |
Windows client | + 20% |
Number of clients (Uniform) | Multiply By # of Clients |
Average directory size larger than 100 objects | + 10% |
Special application dirwalk | + 20% |
Object-sharing R/W | + 20% |