Affinity-aware parallel zeroing of memory for initialization of large pages in non-uniform memory access (numa) servers

Patent metadata

Field	Value
Publication number	US-2016378388-A1
Application number	US-201514883304-A
Country	US
Kind code	A1
Filing date	Oct 14, 2015
Priority date	Jun 25, 2015
Publication date	Dec 29, 2016
Grant date	—

Abstract

Embodiments disclosed herein generally relate to techniques for zeroing memory in computing systems where access to memory is non-uniform. Embodiments include a system having a processor and a memory storing a program; and other embodiments include a computer readable medium containing a program. When executed on a processor, the program causes the processor to perform an operation that includes receiving, via a system call, a request for a pool of memory. The operation also includes determining a size of the requested pool of memory, and creating a dummy memory segment. The size of the dummy memory segment is larger than the size of the requested pool of memory. The operation further includes filling the dummy memory segment with one or more pages, based on the determined size of the requested pool of memory, and deleting the dummy memory segment.

First claim

1 .- 7 . (canceled)

8 . A system, comprising:
a processor; and a memory containing a program which, when executed on the processor, performs an operation, the operation comprising:
receiving, via a system call, a request for a pool of memory;
determining a size of the requested pool of memory;
creating a dummy memory segment, wherein a size of the dummy memory segment is larger than the size of the requested pool of memory;
filling the dummy memory segment with one or more pages, based on the determined size of the requested pool of memory; and
deleting the dummy memory segment.

9 . The system of claim 8 , wherein deleting the dummy memory segment comprises:
sorting the one or more pages of the dummy memory segment according to each of the one or more pages associated affinity domain, wherein each affinity domain comprises a cluster of processors and memory local to the cluster of processors; sending requests to zero the sorted one or more pages to one or more software threads that are attached to the respective affinity domain; and waiting, after sending the requests, to return to a system caller until a message is received, from the software threads in each affinity domain, indicating that all requests to zero have been processed.

10 . The system of claim 8 , wherein deleting the dummy memory segment comprises:
transmitting a request to zero the dummy memory segment to an intermediate software thread; using the intermediate software thread to perform the request as a background process; and upon receiving a message from the intermediate software thread, returning to a system caller, while performing the request, via the intermediate software thread, continues in the background.

11 . The system of claim 8 , wherein the request for the pool of memory comprises a request to grow the pool of memory.

12 . The system of claim 11 , wherein determining the size of the requested pool of memory is based on a size that the pool of memory is requested to grow by.

13 . The system of claim 8 , wherein the request for the pool of memory comprises a request to create the pool of memory.

14 . The system of claim 13 , wherein determining the size of the requested pool of memory is based on a size of the pool of memory that needs to be created.

15 . A computer-readable storage medium storing instructions, which, when executed on a processor, perform an operation, the operation comprising:
receiving, via a system call, a request for a pool of memory; determining a size of the requested pool of memory; creating a dummy memory segment, wherein a size of the dummy memory segment is larger than the size of the requested pool of memory; filling the dummy memory segment with one or more pages, based on the determined size of the requested pool of memory; and deleting the dummy memory segment.

16 . The computer-readable storage medium of claim 15 , wherein deleting the dummy memory segment comprises:
sorting the one or more pages of the dummy memory segment according to each of the one or more pages associated affinity domain, wherein each affinity domain comprises a cluster of processors and memory local to the cluster of processors; sending requests to zero the sorted one or more pages to one or more software threads that are attached to the respective affinity domain; and waiting, after sending the requests, to return to a system caller until a message is received, from the software threads in each affinity domain, indicating that all requests to zero have been processed.

17 . The computer-readable storage medium of claim 15 , wherein deleting the dummy memory segment comprises:
transmitting a request to zero the dummy memory segment to an intermediate software thread; using the intermediate software thread to perform the request as a background process; and upon receiving a message from the intermediate software thread, returning to a system caller, while performing the request, via the intermediate software thread, continues in the background.

18 . The computer-readable storage medium of claim 15 , wherein the request for the pool of memory comprises a request to grow the pool of memory.

19 . The computer-readable storage medium of claim 18 , wherein determining the size of the requested pool of memory is based on a size that the pool of memory is requested to grow by.

20 . The computer-readable storage medium of claim 15 , wherein the request for the pool of memory comprises a request to create the pool of memory, and wherein determining the size of the requested pool of memory is based on a size of the pool of memory that needs to be created.

Assignees

• IBM

Inventors

• Hegde Nakhil
• Mealey Bruce
• Rogers Mark D

Classifications

• G06F9/5016

  the resource being the memory · CPC title

• G06F12/1009 Primary

  using page tables, e.g. page table structures · CPC title

• G06F3/0644

  Management of space entities, e.g. partitions, extents, pools · CPC title

• G06F1/24 Primary

  Resetting means · CPC title

• G06F3/0602

  specifically adapted to achieve a particular effect · CPC title