1*699cd480SApple OSS Distributions<h2>memory_object_perf_info</h2> 2*699cd480SApple OSS Distributions<hr> 3*699cd480SApple OSS Distributions<p> 4*699cd480SApple OSS Distributions<strong>Structure</strong> - Specifies a memory object's attributes with respect to performance. 5*699cd480SApple OSS Distributions<h3>SYNOPSIS</h3> 6*699cd480SApple OSS Distributions<pre> 7*699cd480SApple OSS Distributions<strong>struct memory_object_perf_info</strong> 8*699cd480SApple OSS Distributions<strong>{</strong> 9*699cd480SApple OSS Distributions <strong>vm_offset_t</strong> <var>cluster_size</var><strong>;</strong> 10*699cd480SApple OSS Distributions <strong>boolean_t</strong> <var>may_cache_object</var><strong>;</strong> 11*699cd480SApple OSS Distributions<strong>};</strong> 12*699cd480SApple OSS Distributions 13*699cd480SApple OSS Distributions<strong>typedef struct memory_object_perf_info* memory_object_perf_info_t;</strong> 14*699cd480SApple OSS Distributions</pre> 15*699cd480SApple OSS Distributions<h3>FIELDS</h3> 16*699cd480SApple OSS Distributions<dl> 17*699cd480SApple OSS Distributions<dt> <var>cluster_size</var> 18*699cd480SApple OSS Distributions<dd> 19*699cd480SApple OSS DistributionsPreferred cluster size (in bytes) for the memory object. This helps to 20*699cd480SApple OSS Distributionsdetermine how many pages are transferred in individual data request 21*699cd480SApple OSS Distributionsand return messages. 22*699cd480SApple OSS Distributions<p> 23*699cd480SApple OSS Distributions<dt> <var>may_cache_object</var> 24*699cd480SApple OSS Distributions<dd> 25*699cd480SApple OSS DistributionsCache indicator. If true, the kernel can cache data associated with the 26*699cd480SApple OSS Distributionsmemory object (keep the memory object active) even if no virtual 27*699cd480SApple OSS Distributionsmemory references to it remain. 28*699cd480SApple OSS Distributions</dl> 29*699cd480SApple OSS Distributions<h3>DESCRIPTION</h3> 30*699cd480SApple OSS Distributions<p> 31*699cd480SApple OSS DistributionsThe <strong>memory_object_perf_info</strong> structure 32*699cd480SApple OSS Distributionsdefines a memory object's character with respect to performance. 33*699cd480SApple OSS Distributions<h3>NOTES</h3> 34*699cd480SApple OSS Distributions<p> 35*699cd480SApple OSS DistributionsSharing cached data among all the clients of a memory object can have a major 36*699cd480SApple OSS Distributionsimpact on performance, especially if it can be extended across successive, as 37*699cd480SApple OSS Distributionswell as concurrent, uses. For example, the memory objects that represent 38*699cd480SApple OSS Distributionsprogram images can be used regularly by different programs. 39*699cd480SApple OSS DistributionsBy retaining the data 40*699cd480SApple OSS Distributionsfor these memory objects in cache, the number of secondary storage accesses 41*699cd480SApple OSS Distributionscan be reduced significantly. 42*699cd480SApple OSS Distributions<h3>RELATED INFORMATION</h3> 43*699cd480SApple OSS Distributions<p> 44*699cd480SApple OSS DistributionsFunctions: 45*699cd480SApple OSS Distributions<a href="MO_get_attributes.html"><strong>memory_object_get_attributes</strong></a>, 46*699cd480SApple OSS Distributions<a href="MO_change_attributes.html"><strong>memory_object_change_attributes</strong></a>, 47*699cd480SApple OSS Distributions<a href="vm_region.html"><strong>vm_region</strong></a>, 48*699cd480SApple OSS Distributions<a href="memory_object_synchronize.html"><strong>memory_object_synchronize</strong></a>, 49*699cd480SApple OSS Distributions<a href="VSD_memory_manager.html"><strong>vm_set_default_memory_manager</strong></a>, 50*699cd480SApple OSS Distributions<a href="vm_msync.html"><strong>vm_msync</strong></a>. 51*699cd480SApple OSS Distributions<p> 52*699cd480SApple OSS DistributionsStructures: 53*699cd480SApple OSS Distributions<a href="memory_object_attr_info.html"><strong>memory_object_attr_info</strong></a>. 54