High use of cache memory Post: 302372408

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Top Forums UNIX for Dummies Questions & Answers High use of cache memory Post 302372408 by thegeek on Wednesday 18th of November 2009 12:24:57 AM

11-18-2009

Banned

Code:

 The first row, labeled Mem, displays physical memory utilization, including the amount of memory allocated to buffers and caches.
A buffer, also called buffer memory, is usually defined as a portion of memory that is set aside as a temporary holding place for 
data that is being sent to or received from an external device, such as a HDD, keyboard,
printer or network.  
   The second line of data, which begins with -/+ buffers/cache, shows the amount of physical memory currently devoted to system buffer 
cache. This is particularly meaningful with regard to application programs, as all data 
accessed from files on the system that are performed through the use of read() and write() 
system calls1 pass through this cache. This cache can greatly speed up access to data 
by reducing or eliminating the need to read from or write to the HDD or other disk.

From the web page: How to use the "free" command, by The Linux Information Project (LINFO)

Hope it helps.

thegeek

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LEARN ABOUT PHP

wincache_fcache_meminfo

WINCACHE_FCACHE_MEMINFO(3)						 1						WINCACHE_FCACHE_MEMINFO(3)

wincache_fcache_meminfo - Retrieves information about file cache memory usage

SYNOPSIS

       array wincache_fcache_meminfo (void  )

DESCRIPTION

	Retrieves information about memory usage by file cache.

RETURN VALUES

	Array of meta data about file cache memory usage or FALSE on failure

	The array returned by this function contains the following elements:

	      o memory_total - amount of memory in bytes allocated for the file cache

	      o memory_free - amount of free memory in bytes available for the file cache

	      o num_used_blks - number of memory blocks used by the file cache

	      o num_free_blks - number of free memory blocks available for the file cache

	      o memory_overhead - amount of memory in bytes used for the file cache internal structures

EXAMPLES

       Example #1

	      A wincache_fcache_meminfo(3) example

	      <pre>
	      <?php
	      print_r(wincache_fcache_meminfo());
	      ?>
	      </pre>

	      The above example will output:

	      Array
	      (
		  [memory_total] => 134217728
		  [memory_free] => 131339120
		  [num_used_blks] => 361
		  [num_free_blks] => 3
		  [memory_overhead] => 5856
	      )

SEE ALSO

       wincache_fcache_fileinfo(3),  wincache_ocache_fileinfo(3),  wincache_ocache_meminfo(3),	wincache_rplist_fileinfo(3),  wincache_rplist_mem-
       info(3), wincache_refresh_if_changed(3), wincache_ucache_meminfo(3), wincache_ucache_info(3), wincache_scache_info(3), wincache_scache_mem-
       info(3).

PHP Documentation Group 												WINCACHE_FCACHE_MEMINFO(3)

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