Memory
Asa baseline, Web Server requires 64 MB RAM. Multiple CPUs require at least 64 MB for each
CPU.For example, if you have four CPUs, you should install at least 256 MB RAM for optimal
performance.For high numbers of peak concurrent users, also allow extra RAM for the
additionalthreads. After the rst 50 concurrent users, add an extra 512 KB for each peak
concurrentuser.
DriveSpace
Youneed to have enough drive space for your OS, document tree, and log les. In most cases, 2
GBtotal is sucient.
Putthe OS, swap/paging le, Web Server logs, and document tree each on separate hard drives.
Ifyour log les ll up the log drive, your OS does not suer. Also, you’ll be able to tell whether,
forexample, the OS paging le is causing drive activity.
YourOS vendor might have specic recommendations for how much swap or paging space you
shouldallocate. Based on testing, Web Server performs best with swap space equal to RAM,
plusenough to map the document tree.
Networking
Foran Internet site, decide how many peak concurrent users you need the server to handle, and
multiplythat number of users by the average request size on your site. Your average request
mightinclude multiple documents. If you’re not sure, try using your home page and all of its
associatedsubframes and graphics.
Nextdecide how long the average user will be willing to wait for a document, at peak utilization.
Divideby that number of seconds. That’s the WAN bandwidth your server needs.
Forexample, to support a peak of 50 users with an average document size of 24 KB, and
transferringeach document in an average of 5 seconds, 240 KBs (1920 Kbit/s) are needed.
Therefore,our site needs two T1 lines (each 1544 Kbit/s). This also allows some overhead for
growth.
Yourserver’s network interface card should support more than the WAN to which it’s
connected.For example, if you have up to three T1 lines, you can get by with a 10BaseT
interface.Up to a T3 line (45 Mbit/s), you can use 100BaseT. But if you have more than 50
Mbit/sof WAN bandwidth, consider conguring multiple 100BaseT interfaces, or look at
GigabitEthernet technology.
Foran intranet site, your network is unlikely to be a bottleneck. However, you can use the same
calculationsas above to verify this.
Memory
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