On Sun, Oct 31, 2004 at 05:49:45PM -0700, James McKenzie wrote: > I would recommend, with 128MB of ram, making your swap at least 256MB. > I would more lean towards 512MB if you are running X. Actually, I would > highly recommend against running X if you have less than 256MB of ram > due to the requirements for X and most X based programs. > > James McKenzie > > Mike Witt wrote: > > >My newly installed FC2 systems is running a lot slower than > >I expected. I chose the "default" partitioning scheme suggested > >during installation. And fdisk now reports this as: Do not be concerned that the default swap partition is small. You can always add swap files at a later date. It can be important to have a largish swap file simply because kernel bookkeeping can demand that there be resources to satisfy the implicit reservation. There is a real life analogy worth sharing. If you are traveling and check into a hotel for a week or a month. The hotel will run your credit card and preapproved not only the room but in many cases they will preapprove enough to cover the mini bar, restaurant and more. Now you take the same credit card out of the hotel and in a fine restaurant find that you no longer have any credit on the card so you use another card. The day after you check out from the hotel the large preapproval amount is replaced with a smaller amount that reflects the real amount. In linux I can "malloc()" a large chunk of memory and attempt a fork(); exec() sequence. It is possible that the fork() will fail because there is not enough virtual memory to hold the two copies of the process as specified by fork() semantics. The Mallory() memory may never have been touched, simply reserved. The equivalent is that you are now over drawn at the virtual memory bank and have exceeded your credit line. None of the above malloc() and fork();exec() sequences needs very much additional physical memory but the system must reserve the additional resources because that is the contract implicit in the system call.... The BSD folks added the vfork() system call to give the system some hint that the full reservation of memory is not needed. There is a kernel option for lazy kernel memory book keeping. I do not recommend that it be used .... Go with the defaults and add swap files if needed. -- T o m M i t c h e l l May your cup runneth over with goodness and mercy and may your buffers never overflow.
