초록 ▼

In a method and system for dynamically improving the performance of a server in a network, a tuning system monitors a workload of the server in real time, monitors a set of internal performance characteristics of the server in real time, and monitors a set of adjustable server parameters of the serv

In a method and system for dynamically improving the performance of a server in a network, a tuning system monitors a workload of the server in real time, monitors a set of internal performance characteristics of the server in real time, and monitors a set of adjustable server parameters of the server in real time. The workload of the server may include the frequency and type of service requests received by the server from clients in the network. The internal server performance characteristics may include, for example, a data cache hit ratio of a data cache in the server. The set of server parameters may include, for example, the overall data cache size or the data cache geometry of the server. The tuning system periodically alters one or more of the set of adjustable server parameters as a function of the workload and internal performance characteristics of the server. Since the tuning system is continuously monitoring workload and performance characteristics of the server and altering the server parameters accordingly, the effectiveness of a given change in the server parameters is reflected in the next set of monitored workload and performance values.

대표청구항 ▼

[ What is claimed is:] [1.] A method of operating a data cache, comprising the steps of:maintaining clean and dirty data buffers in the data cache, clean buffers containing only data received from a backing store containing a copy of the data, dirty buffers containing data received from a data sourc

[ What is claimed is:] [1.] A method of operating a data cache, comprising the steps of:maintaining clean and dirty data buffers in the data cache, clean buffers containing only data received from a backing store containing a copy of the data, dirty buffers containing data received from a data source other than the backing store and intended to be written to the backing store but not yet so written;monitoring the ratio of clean buffers to the sum of clean and dirty buffers in the data cache;maintaining a data cache flushing threshold R.sub.c representing a minimum desirable ratio of clean buffers to the sum of clean and dirty buffers;flushing dirty buffers from the data cache to the backing store in response to the condition that the ratio of clean buffers to the sum of clean and dirty buffers in the data cache is less than R.sub.c ;periodically monitoring the following statistics pertaining to operation of the data cache: (a) a flushing rate representing the rate at which dirty buffers are being flushed from the data cache to the backing store, and (b) the numbers of read operations and write operations received by the data cache in the most recent monitoring period;calculating an average read rate N.sub.r-avg and an average write rate N.sub.w-avg from the monitored numbers of read and write operations;determining whether the flushing rate is exhibiting saturation behavior;for the following sets of conditions, performing the corresponding steps:if the flushing rate has changed over a first number of preceding periods but is not exhibiting saturation behavior, then setting R.sub.c to a new value equal to the ratio of N.sub.r-avg to the sum of N.sub.r-avg and N.sub.w-avg ;if the flushing rate is exhibiting saturation behavior, then setting R.sub.c to a new value equal to either (i) the ratio of N.sub.r-avg to the sum of N.sub.r-avg and N.sub.w-avg, if that ratio is less than R.sub.c, or (ii) 80% of R.sub.c otherwise; andif the flushing rate has not changed over the first number of preceding periods, then refraining from changing the value of R.sub.c.