公开(公告)号：US07606989B1

公开(公告)日：2009-10-20

申请号：US11218145

申请日：2005-09-01

Applicant: David L. Detlefs ,  Antonios Printezis ,  Fabio Rojas

Inventor： David L. Detlefs ,  Antonios Printezis ,  Fabio Rojas

IPC: G06F13/00

CPC classification number: G06F12/0276

Abstract: In a generational garbage collector, a decision is made to pre-tenure, or allocate new objects directly in the old generation, by a two step process. In the first step, during a young-generation collection, the number of bytes that survive collection is determined for each allocation site and a predetermined number of sites with the highest number of surviving bytes are selected as candidate sites. In the second step, during a subsequent young-generation collection, the survival rates are determined for the candidate sites and objects to be allocated from sites with a sufficiently high survival rate are allocated directly in older generations.

Abstract translation: 在一代代的垃圾收集器中，决定通过两步过程来预授权，或直接在旧一代分配新对象。 在第一步中，在年轻一代的收集中，为每个分配站点确定收集中存储的字节数，并且选择具有最高存活字节数的预定数量的站点作为候选站点。 在第二步，在随后的年轻一代收集中，确定候选地点的存活率，并且将具有足够高的存活率的地点分配的对象直接分配给老一代。

公开(公告)号：US20090248766A1

公开(公告)日：2009-10-01

申请号：US12416043

申请日：2009-03-31

Applicant: Alexander T. Garthwaite ,  Antonios Printezis

Inventor： Alexander T. Garthwaite ,  Antonios Printezis

IPC: G06F12/00 ,  G06F17/30

CPC classification number: G06F12/0276

Abstract: A method for performing garbage collection involves obtaining a first reference bitmap including a block address and a set of mark bits, obtaining a first reference, identifying a mark bit of the set of mark bits based on the first reference, comparing an address associated with the mark bit with the first reference to generate a comparison, selecting an existing word from a global bit map based on the block address and the comparison, calculating a new word based on the set of mark bits and the existing word, replacing the existing word in the global bit map with the new word, and reclaiming a block of memory for reuse based on the global bit map after replacing the existing word.

Abstract translation: 一种用于执行垃圾收集的方法包括获得包括块地址和一组标记位的第一参考位图，获得第一参考，基于第一参考识别该组标记位的标记位，比较与 标记位与第一参考以产生比较，基于块地址和比较从全局位图中选择现有字，基于标记位和现有字的集合来计算新字，替换现有字在 使用新字的全局位图，并且在替换现有单词之后基于全局位图回收用于重用的存储器块。

公开(公告)号：US20080263295A1

公开(公告)日：2008-10-23

申请号：US11787933

申请日：2007-04-18

Applicant: Antonios Printezis ,  Peter B. Kessler

Inventor： Antonios Printezis ,  Peter B. Kessler

IPC: G06F12/00

CPC classification number: G06F12/0253

Abstract: Apparatus, methods, and computer program products are disclosed that improve management of a dynamic memory area. One aspect is a method that reclaims memory referenced by a finalizable-object that has been instantiated from a class definition that incorporates at least one parent class and one or more class-extensions into a class hierarchy. The method includes marking for retention a related memory reachable from a reference field of the finalizable-object, and adding the finalizable-object to a finalization set for subsequent invocation of a non-trivial finalize-method. The method also determines whether the portion of the finalizable-object that includes the reference field to the related memory is a class-extension that has a finalizer-free characteristic and conditions the marking for retention on that determination. Thus, a portion the finalizable-object's related memory can be more quickly reclaimed from a dynamic memory area.

Abstract translation: 公开了改善动态存储器区域的管理的装置，方法和计算机程序产品。 一个方面是回收由已定义的finalizable对象引用的内存的方法，该类定义将至少一个父类和一个或多个类扩展合并到类层次结构中。 该方法包括用于保留从可终结对象的参考字段可访问的相关存储器的标记，以及将可终止对象添加到用于后续调用非平凡终结方法的最终化对象。 该方法还确定包括对相关存储器的参考字段的可终结对象的部分是否具有具有无终结者的特性的类别扩展，并且在该确定的条件下保留标记。 因此，可以从动态存储器区域更快地回收可终结对象的相关存储器的一部分。

公开(公告)号：US20080235305A1

公开(公告)日：2008-09-25

申请号：US11725918

申请日：2007-03-20

Applicant: Antonios Printezis ,  John W. Coomes

Inventor： Antonios Printezis ,  John W. Coomes

IPC: G06F12/00

CPC classification number: G06F12/0253 ,  G06F2212/702

Abstract: A technique for establishing a dense prefix for a memory in a computer system. Memory is divided into a plurality of chunks. An efficiency factor is generated for each chunk in one or more chunks contained in the plurality of chunks. The efficiency factor may be based on an amount of memory to be reclaimed, an amount of memory to be scanned and an amount of memory to be copied relative to the chunk. A dense prefix is then established for the memory based on an efficiency factor associated with a chunk.

Abstract translation: 一种用于为计算机系统中的存储器建立密集前缀的技术。 存储器被分成多个块。 为包含在多个块中的一个或多个块中的每个块生成效率因子。 效率因子可以基于待回收的存储器的量，要被扫描的存储器的量和相对于块被复制的存储器的量。 然后基于与块相关联的效率因子为存储器建立密集前缀。

公开(公告)号：US20080172538A1

公开(公告)日：2008-07-17

申请号：US11654456

申请日：2007-01-17

Applicant: David Dice ,  Antonios Printezis

Inventor： David Dice ,  Antonios Printezis

IPC: G06F12/00

CPC classification number: G06F12/0253

Abstract: A method, apparatus and computer program product for providing page-protection based memory access barrier traps is presented. A value for a user-mode bit (u-bit) is computed for each extant virtual page in an address space, the u-bit indicative that an object on the virtual page is being moved by a Garbage Collector process. An instruction is executed which causes an access protection fault. The state of the u-bit for the virtual page associated with the access protection fault is consulted when the access protection fault is encountered. Additionally, the access protection fault is translated into a user-trap (utrap) and the utrap is serviced when the u-bit is set.

Abstract translation: 提出了一种用于提供基于页面保护的存储器访问障碍阱的方法，装置和计算机程序产品。 为地址空间中的每个现有虚拟页面计算用户模式位（u位）的值，表示虚拟页面上的对象正在被垃圾收集器进程移动的u位。 执行导致访问保护故障的指令。 当遇到访问保护故障时，将查阅与访问保护故障相关联的虚拟页面的u位状态。 另外，访问保护故障被转换为用户陷阱（utrap），并且当u位置1时，接口保护故障被服务。

公开(公告)号：US07136887B2

公开(公告)日：2006-11-14

申请号：US10309503

申请日：2002-12-04

Applicant: Alexander T. Garthwaite ,  David L. Detlefs ,  Antonios Printezis ,  Y. Srinivas Ramakrishna

Inventor： Alexander T. Garthwaite ,  David L. Detlefs ,  Antonios Printezis ,  Y. Srinivas Ramakrishna

IPC: G06F12/12

CPC classification number: G06F12/0269 ,  G06F12/0276 ,  Y10S707/955 ,  Y10S707/99957

Abstract: A garbage collector divides the garbage-collected heap into “cards.” It maintains a table containing a card-object table entry for each card. A card's entry contains information from which the collector can determine where any references in the card are located and thereby identify objects that may be reachable. The encoding of a card's table entry is not restricted to values that indicate the location of the object in which the card begins. Instead, its possible values additionally include ones that indicate that the card begins with a certain number of references or that an object begins at a given location in the middle of the card. The collector thereby avoids consulting object's class information unnecessarily.

Abstract translation: 垃圾收集器将垃圾收集堆分成“卡”。 它维护一个包含每个卡的卡对象表条目的表。 卡的条目包含收集者可以确定卡中的任何引用位置的信息，从而识别可达到的对象。 卡的表项的编码不限于指示卡开始的对象的位置的值。 相反，其可能的值还包括指示卡以特定数量的引用开始的对象或者对象在卡的中间的给定位置开始的值。 收集器避免了不必要地查询对象的类信息。

公开(公告)号：US11099982B2

公开(公告)日：2021-08-24

申请号：US13077619

申请日：2011-03-31

Applicant: Antonios Printezis ,  Igor Veresov ,  Paul Henry Hohensee ,  John Coomes

Inventor： Antonios Printezis ,  Igor Veresov ,  Paul Henry Hohensee ,  John Coomes

IPC: G06F12/00 ,  G06F16/30 ,  G06F12/02

Abstract: Methods and systems for garbage collection are described. In some embodiments, Garbage collector threads may maximize local accesses and minimize remote access by copying Young objects and Old objects differently. When copying a Young object, a garbage collector thread may determine the lgroup of the pool that contains the object and copy the object to a pool of the same lgroup. The garbage collector thread may spread Old objects among lgroups by copying Old objects to pools of the same lgroup as the respective garbage collector thread. Additional methods and systems are disclosed.

公开(公告)号：US10140208B2

公开(公告)日：2018-11-27

申请号：US13077678

申请日：2011-03-31

Applicant: Antonios Printezis ,  Igor Veresov ,  Paul Henry Hohensee ,  John Coomes

Inventor： Antonios Printezis ,  Igor Veresov ,  Paul Henry Hohensee ,  John Coomes

IPC: G06F7/00 ,  G06F12/02

Abstract: System and Methods for non-uniform memory (NUMA) garbage collection are provided. Multiple memories and processors are categorized into local groups. A heap space is divided into multiple pools and stored in each of the memories. Garbage collection threads are assigned to each of the local groups. Garbage collection is performed using the garbage collection threads for objects contained in the pools using the garbage collector threads, memory, and processor assigned to each local group, minimizing remote memory accesses.

公开(公告)号：US08566812B1

公开(公告)日：2013-10-22

申请号：US11514514

申请日：2006-08-31

Applicant: Antonios Printezis ,  Yin Zin Mark Lam

Inventor： Antonios Printezis ,  Yin Zin Mark Lam

IPC: G06F9/45

CPC classification number: G06F9/45558 ,  G06F9/5016 ,  G06F11/3409 ,  G06F11/3466 ,  G06F12/0276 ,  G06F2009/45583 ,  G06F2201/815 ,  G06F2201/865

Abstract: One embodiment of the present invention provides a system that uses observed object patterns to dynamically tune a virtual machine for responsiveness and/or throughput. The system first analyzes a memory region containing a set of objects to identify objects in the memory region that indicate the need for responsiveness and/or throughput. The system gathers statistics based on the identified and unidentified objects in the set of objects, and then uses these statistics to dynamically tune a virtual machine.

Abstract translation: 本发明的一个实施例提供一种使用观察到的对象模式来动态调整虚拟机以响应和/或吞吐量的系统。 系统首先分析包含一组对象的存储器区域，以识别存储器区域中的对象，以指示响应性和/或吞吐量的需要。 系统基于对象集中的已识别和未识别的对象收集统计信息，然后使用这些统计信息来动态调整虚拟机。

公开(公告)号：US07676511B2

公开(公告)日：2010-03-09

申请号：US11340940

申请日：2006-01-27

Applicant: Antonios Printezis ,  David L. Detlefs ,  Fabio Rojas

Inventor： Antonios Printezis ,  David L. Detlefs ,  Fabio Rojas

IPC: G06F17/30

CPC classification number: G06F12/0276

Abstract: In some circumstances a generational garbage collector may be made more efficient by “pre-tenuring” objects or directly allocating new objects in an old generation instead of allocating them in the normal fashion in a young generation. A pre-tenuring decision is made by a two step process. In the first step, during a young-generation collection, an execution frequency is determined for each allocation site and sites with the highest execution frequency are selected as candidate sites. In the second step, during a subsequent young-generation collection, the survival rates are determined for the candidate sites. After this, objects allocated from sites with sufficiently high survival rates are allocated directly in the old generation.

Abstract translation: 在某些情况下，世代垃圾收集器可以通过“预置换”对象或直接分配新的对象，而不是以年轻一代中的正常方式分配，从而更有效率。 通过两步过程进行了一项前期终身决定。 第一步，在年轻一代的收集中，为每个分配站点确定执行频率，并选择具有最高执行频率的站点作为候选站点。 在第二步，在随后的年轻一代收集中，确定候选地点的存活率。 之后，从具有足够高存活率的地点分配的物品直接分配给老一代。