This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

[v3] libstdc++/29179


Hi,

committed to mainline and 4_1-branch.

Paolo.

///////////////////
2006-09-25  Paolo Carlini  <pcarlini@suse.de>

	PR libstdc++/29179
	* include/ext/mt_allocator.h (__pool_base): Adjust/extend
	documentation in comments.
Index: include/ext/mt_allocator.h
===================================================================
--- include/ext/mt_allocator.h	(revision 117183)
+++ include/ext/mt_allocator.h	(working copy)
@@ -50,7 +50,7 @@
   struct __pool_base
   {
     // Using short int as type for the binmap implies we are never
-    // caching blocks larger than 65535 with this allocator.
+    // caching blocks larger than 32768 with this allocator.
     typedef unsigned short int _Binmap_type;
 
     // Variables used to configure the behavior of the allocator,
@@ -73,19 +73,23 @@
       // Allocation requests (after round-up to power of 2) below
       // this value will be handled by the allocator. A raw new/
       // call will be used for requests larger than this value.
+      // NB: Must be much smaller than _M_chunk_size and in any
+      // case <= 32768.
       size_t	_M_max_bytes; 
-      
+
       // Size in bytes of the smallest bin.
-      // NB: Must be a power of 2 and >= _M_align.
+      // NB: Must be a power of 2 and >= _M_align (and of course
+      // much smaller than _M_max_bytes).
       size_t	_M_min_bin;
-      
+
       // In order to avoid fragmenting and minimize the number of
       // new() calls we always request new memory using this
       // value. Based on previous discussions on the libstdc++
       // mailing list we have choosen the value below.
       // See http://gcc.gnu.org/ml/libstdc++/2001-07/msg00077.html
+      // NB: At least one order of magnitude > _M_max_bytes. 
       size_t	_M_chunk_size;
-      
+
       // The maximum number of supported threads. For
       // single-threaded operation, use one. Maximum values will
       // vary depending on details of the underlying system. (For
@@ -93,7 +97,7 @@
       // /proc/sys/kernel/threads-max, while Linux 2.6.6 reports
       // 65534)
       size_t 	_M_max_threads;
-      
+
       // Each time a deallocation occurs in a threaded application
       // we make sure that there are no more than
       // _M_freelist_headroom % of used memory on the freelist. If

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]