DZone
Thanks for visiting DZone today,
Edit Profile
  • Manage Email Subscriptions
  • How to Post to DZone
  • Article Submission Guidelines
Sign Out View Profile
  • Post an Article
  • Manage My Drafts
Over 2 million developers have joined DZone.
Log In / Join
Refcards Trend Reports Events Over 2 million developers have joined DZone. Join Today! Thanks for visiting DZone today,
Edit Profile Manage Email Subscriptions Moderation Admin Console How to Post to DZone Article Submission Guidelines
View Profile
Sign Out
Refcards
Trend Reports
Events
Zones
Culture and Methodologies Agile Career Development Methodologies Team Management
Data Engineering AI/ML Big Data Data Databases IoT
Software Design and Architecture Cloud Architecture Containers Integration Microservices Performance Security
Coding Frameworks Java JavaScript Languages Tools
Testing, Deployment, and Maintenance Deployment DevOps and CI/CD Maintenance Monitoring and Observability Testing, Tools, and Frameworks
Culture and Methodologies
Agile Career Development Methodologies Team Management
Data Engineering
AI/ML Big Data Data Databases IoT
Software Design and Architecture
Cloud Architecture Containers Integration Microservices Performance Security
Coding
Frameworks Java JavaScript Languages Tools
Testing, Deployment, and Maintenance
Deployment DevOps and CI/CD Maintenance Monitoring and Observability Testing, Tools, and Frameworks
  1. DZone
  2. Software Design and Architecture
  3. Performance
  4. Memory Management Goop in Windows and Linux

Memory Management Goop in Windows and Linux

Get some insight on the different ways Windows and Linux manage memory.

Oren Eini user avatar by
Oren Eini
·
Oct. 29, 18 · Opinion
Like (1)
Save
Tweet
Share
3.17K Views

Join the DZone community and get the full member experience.

Join For Free

Regardless of the operating system you use, you are going to get roughly the same services from each of them. In particular, process and memory isolation, managing the hardware, etc. It can sometimes be really interesting to see the difference between the operating systems approach to solving the same problem. Case in point, how both Windows and Linux manage memory. Both of them run on the same hardware and do roughly the same thing. But they have very different styles, this ends up having profound implications on the application using them.

Consider what appears to be a very simple question, what stuff do I have in my RAM? Linux keeps track of Resident Set Size on a per-mapping basis, which means that we are able to figure out how much of a mmap file is actually in memory. Furthermore, we can figure out how much of the mmap data is clean, which means that it is easily discardable and how much is dirty and needs to be written to disk. Linux exposes this information via the /proc/[pid]/smaps.

On the other hand, Windows doesn’t seem to bother to do this tracking. You can get this information, but you need to ask it for each page individually. This means that it isn’t feasible to check what percentage of the system memory is clean (mmap pages that haven’t been modified and can be cheaply discarded). Windows expose this via the QueryWorkingSetEx method.

As a result, we have to be more conservative on Windows when the system reports high memory usage. We know that our usage pattern means a high amount of memory in use (coming from mmap clean pages) is fine. It is a small detail, but it has caused us to have to jump through several hurdles when we are running under load. I guess that Windows doesn’t need this information, so it isn’t exposed, while on Linux, it seems to be used by plenty of callers.

Memory (storage engine) Linux (operating system) operating system

Published at DZone with permission of Oren Eini, DZone MVB. See the original article here.

Opinions expressed by DZone contributors are their own.

Popular on DZone

  • Deploying Java Serverless Functions as AWS Lambda
  • Building a Scalable Search Architecture
  • How to Secure Your CI/CD Pipeline
  • Java Development Trends 2023

Comments

Partner Resources

X

ABOUT US

  • About DZone
  • Send feedback
  • Careers
  • Sitemap

ADVERTISE

  • Advertise with DZone

CONTRIBUTE ON DZONE

  • Article Submission Guidelines
  • Become a Contributor
  • Visit the Writers' Zone

LEGAL

  • Terms of Service
  • Privacy Policy

CONTACT US

  • 600 Park Offices Drive
  • Suite 300
  • Durham, NC 27709
  • support@dzone.com
  • +1 (919) 678-0300

Let's be friends: