1*27b03b36SApple OSS Distributions<h2>memory_object_perf_info</h2> 2*27b03b36SApple OSS Distributions<hr> 3*27b03b36SApple OSS Distributions<p> 4*27b03b36SApple OSS Distributions<strong>Structure</strong> - Specifies a memory object's attributes with respect to performance. 5*27b03b36SApple OSS Distributions<h3>SYNOPSIS</h3> 6*27b03b36SApple OSS Distributions<pre> 7*27b03b36SApple OSS Distributions<strong>struct memory_object_perf_info</strong> 8*27b03b36SApple OSS Distributions<strong>{</strong> 9*27b03b36SApple OSS Distributions <strong>vm_offset_t</strong> <var>cluster_size</var><strong>;</strong> 10*27b03b36SApple OSS Distributions <strong>boolean_t</strong> <var>may_cache_object</var><strong>;</strong> 11*27b03b36SApple OSS Distributions<strong>};</strong> 12*27b03b36SApple OSS Distributions 13*27b03b36SApple OSS Distributions<strong>typedef struct memory_object_perf_info* memory_object_perf_info_t;</strong> 14*27b03b36SApple OSS Distributions</pre> 15*27b03b36SApple OSS Distributions<h3>FIELDS</h3> 16*27b03b36SApple OSS Distributions<dl> 17*27b03b36SApple OSS Distributions<dt> <var>cluster_size</var> 18*27b03b36SApple OSS Distributions<dd> 19*27b03b36SApple OSS DistributionsPreferred cluster size (in bytes) for the memory object. This helps to 20*27b03b36SApple OSS Distributionsdetermine how many pages are transferred in individual data request 21*27b03b36SApple OSS Distributionsand return messages. 22*27b03b36SApple OSS Distributions<p> 23*27b03b36SApple OSS Distributions<dt> <var>may_cache_object</var> 24*27b03b36SApple OSS Distributions<dd> 25*27b03b36SApple OSS DistributionsCache indicator. If true, the kernel can cache data associated with the 26*27b03b36SApple OSS Distributionsmemory object (keep the memory object active) even if no virtual 27*27b03b36SApple OSS Distributionsmemory references to it remain. 28*27b03b36SApple OSS Distributions</dl> 29*27b03b36SApple OSS Distributions<h3>DESCRIPTION</h3> 30*27b03b36SApple OSS Distributions<p> 31*27b03b36SApple OSS DistributionsThe <strong>memory_object_perf_info</strong> structure 32*27b03b36SApple OSS Distributionsdefines a memory object's character with respect to performance. 33*27b03b36SApple OSS Distributions<h3>NOTES</h3> 34*27b03b36SApple OSS Distributions<p> 35*27b03b36SApple OSS DistributionsSharing cached data among all the clients of a memory object can have a major 36*27b03b36SApple OSS Distributionsimpact on performance, especially if it can be extended across successive, as 37*27b03b36SApple OSS Distributionswell as concurrent, uses. For example, the memory objects that represent 38*27b03b36SApple OSS Distributionsprogram images can be used regularly by different programs. 39*27b03b36SApple OSS DistributionsBy retaining the data 40*27b03b36SApple OSS Distributionsfor these memory objects in cache, the number of secondary storage accesses 41*27b03b36SApple OSS Distributionscan be reduced significantly. 42*27b03b36SApple OSS Distributions<h3>RELATED INFORMATION</h3> 43*27b03b36SApple OSS Distributions<p> 44*27b03b36SApple OSS DistributionsFunctions: 45*27b03b36SApple OSS Distributions<a href="MO_get_attributes.html"><strong>memory_object_get_attributes</strong></a>, 46*27b03b36SApple OSS Distributions<a href="MO_change_attributes.html"><strong>memory_object_change_attributes</strong></a>, 47*27b03b36SApple OSS Distributions<a href="vm_region.html"><strong>vm_region</strong></a>, 48*27b03b36SApple OSS Distributions<a href="memory_object_synchronize.html"><strong>memory_object_synchronize</strong></a>, 49*27b03b36SApple OSS Distributions<a href="VSD_memory_manager.html"><strong>vm_set_default_memory_manager</strong></a>, 50*27b03b36SApple OSS Distributions<a href="vm_msync.html"><strong>vm_msync</strong></a>. 51*27b03b36SApple OSS Distributions<p> 52*27b03b36SApple OSS DistributionsStructures: 53*27b03b36SApple OSS Distributions<a href="memory_object_attr_info.html"><strong>memory_object_attr_info</strong></a>. 54