Chapter 2 HPSS Planning134 September 2002 HPSS Installation GuideRelease 4.5, Revision 22.10.3.2.8 Disk Space Requirements for Running NFS DaemonThe HPSS NFS server memory and disk space requirements are largely determined by theconfiguration of the NFS request processing, attribute cache, and data cache. Data cache memoryrequirements can be estimated by multiplying the data cache buffer size by the number of memorydata cache buffers.Attribute cache memory requirements can be estimated by combining requirements for directoryname with file attribute memory requirements. The total number of name space objects kept in theNFS attribute cache is determined by the maximum number of entries in the attribute cache leastrecently used (LRU) list. A portion of these entries will be directories, and the rest will be bitfiles,symbolic links, or hard links.Directory name memory requirements are determined by multiplying the estimated number ofcached directories by the directory size configuration. Estimating the number of cached directoriescan be done by multiplying the number of entries in the attribute cache LRU list by the percentageof directories to files at the site. For example, if the LRU list maximum is set to 100 and thepercentage of directories at the site is 1 directory to 10 files (10%), the estimated number of cacheddirectories is 10.File attribute memory requirements are determined by subtracting the number of cacheddirectories from the maximum number of entries on the LRU list and multiplying the result by 100.Request processing memory requirements can be estimated by multiplying the number of ONCremote procedure call threads by 65 KB.The HPSS NFS Server requires disk storage for five UNIX files:• Exports file—a text file that specifies how NFS access is offered.• Remote mount (rmtab) file—this file, in the same directory as the exports file, is a text filethat identifies what clients have mounted HPSS directories.• Credentials map file—a text file that is used to checkpoint the NFS credentials map. Thecredentials map file size will be based on the number of entries in the credentials mapcache.• Checkpoint file—required by the data cache. The data cache checkpoint file size is relatedto the number of cache entries, but is much smaller than the cache entry file.• Entry file—required by the data cache. Disk storage for the data cache entry file isdetermined by multiplying the number of cache entries by the data cache buffer size. Thedata cache entry file should be placed in its own disk partition to avoid disk contention.2.10.3.2.9 Disk Space Requirements for Running SSMIf SSM is configured to buffer alarm and event messages in a disk file, each SSM Data Server processwill require an alarm file approximately 5MB in size. This file may be placed wherever it isconvenient. There is normally only one Data Server process.
