Affinity aware parallel zeroing of memory in non-uniform memory access (NUMA) servers

Patent metadata

Field	Value
Publication number	US-10241550-B2
Application number	US-201715824463-A
Country	US
Kind code	B2
Filing date	Nov 28, 2017
Priority date	Jun 25, 2015
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

A method for zeroing memory in computing systems where access to memory is non-uniform includes receiving, via a system call, a request for a pool of memory, 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 dummy memory segment is filled with one or more pages, based on the determined size of the requested pool of memory, and the dummy memory segment is deleted.

First claim

What is claimed is:

1. 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, wherein deleting the dummy memory segment comprises:
sorting the one or more pages of the dummy memory segment according to each associated affinity domain of each page, 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 for a message, from the software threads in each affinity domain, indicating that all requests to zero have been processed before returning to a system caller of the system call.

2. The system of claim 1 , wherein the request for the pool of memory comprises a request to grow the pool of memory.

3. The system of claim 2 , wherein the size of the requested pool of memory is determined based on a size that the pool of memory is requested to grow by.

4. The system of claim 1 , wherein the request for the pool of memory comprises a request to create the pool of memory.

5. The system of claim 4 , wherein the size of the requested pool of memory is determined based on a size of the pool of memory that needs to be created.

6. 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, wherein deleting the dummy memory segment comprises:
transmitting a request to zero the one or more pages in the dummy memory segment to an intermediate software thread;
using the intermediate software thread to perform the request as a background process, comprising:
sorting the one or more pages of the dummy memory segment according to each associated affinity domain of each page, each affinity domain comprising 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 additional software threads that are attached to the respective affinity domain; and
receiving, from each of the one or more additional software threads, notifications that the requests to zero the sorted one or more pages have been processed; 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.

7. The system of claim 6 , wherein the request for the pool of memory comprises a request to grow the pool of memory.

8. The system of claim 7 , wherein the size of the requested pool of memory is determined based on a size that the pool of memory is requested to grow by.

9. The system of claim 6 , wherein the request for the pool of memory comprises a request to create the pool of memory.

10. The system of claim 9 , wherein the size of the requested pool of memory is determined based on a size of the pool of memory that needs to be created.

11. A non-transitory 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, wherein deleting the dummy memory segment comprises:
sorting the one or more pages of the dummy memory segment according to each associated affinity domain of each page, 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 for a message, from the software threads in each affinity domain, indicating that all requests to zero have been processed before returning to a system caller of the system call.

12. The non-transitory computer-readable storage medium of claim 11 , wherein the request for the pool of memory comprises a request to grow the pool of memory.

13. The non-transitory computer-readable storage medium of claim 12 , wherein the size of the requested pool of memory is determined based on a size that the pool of memory is requested to grow by.

14. The non-transitory computer-readable storage medium of claim 11 , wherein the request for the pool of memory comprises a request to create the pool of memory.

15. The non-transitory computer-readable storage medium of claim 14 , wherein the size of the requested pool of memory is determined based on a size of the pool of memory that needs to be created.

Assignees

• IBM

Inventors

• Hegde Nikhil
• Mealey Bruce
• Rogers Mark D

Classifications

• G06F3/0644

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

• G06F12/023

  Free address space management · CPC title

• G06F2212/2542

  Non-uniform memory access [NUMA] architecture · CPC title

• G06F12/1009 Primary

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

• G06F2212/1044

  Space efficiency improvement · CPC title