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Chapter 1Depending on your system I/O load, partitions can be placed on different physicaldisks. The benefit of this placement is better I/O performance, especially on /varand /tmp partitions. You can also create /tmp in your system RAM by tweaking thetmpmfs variable in /etc/rc.conf file. An example of such a configuration wouldlook like this:tmpmfs="YES"tmpsize="128m"This will mount a 128 MB partition onto RAM using md(4) driver so that accessto /tmp would be dramatically faster, especially for programs which constantlyread/write temporary data into /tmp directory.SwapSwap space is a very important part of the virtual memory system. Despite thefact that most servers are equipped with enough physical memory, having enoughswap space is still very important for servers with high and unexpected loads. It isrecommended that you distribute swap partitions across multiple physical disks orcreate the swap partition on a separate disk, to gain better performance. FreeBSDautomatically uses multiple swap partitions (if available) in a round-robin fashion.When installing a new FreeBSD system, you can use disklabel editor to createappropriate swap partitions. Creating a swap partition, which is double the size ofthe installed physical memory, is a good rule of thumb.Using swapinfo(8) and pstat(8) commands, you can review your current swapconfiguration and status. The swapinfo(8) command displays the system's currentswap statistics as follows:# swapinfo –hDevice 1K-blocks Used Avail Capacity/dev/da0s1b 4194304 40K 4.0G 0%The pstat(8) command has more capabilities as compared with the swapinfo(8)command and shows the size of different system tables, under different loadconditions. This is shown in the following command line:# pstat –T176/12328 files0M/4096M swap space[ ]