> Generally, adding extra memory won't improve I/O throughput (reduce I/O > wait > times) unless the application characteristics are such that you get decent > benefits from readahead and caching to avoid buffer recycling trashing > data > you are going to need soon. For database applications (where feasible) it > is obviously an advantage if you can fit the working data set in core > memory, > utilizing it as a large write-through cache.
The way QDIO device handling works, the size of the transfer buffers affect the amount of information that can be moved with a single operation, which sets a maximum limit on the transfer rate for a fixed processor speed. Analagous to DMA buffer size; not main storage allocation, but managing link congestion by controlling transmit/receive buffers and window size. ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
