How does windows do filesystem caching?

March 18, 2009 6:23 PM

How does windows do filesystem caching?

When I mount NTFS via linux, the performance is much slower than when i used window. How does windows handle the filesystem caching? I am not talking about file indexing/searching, but read/write performance. Is it a service? A method?

posted by torpark to computers & internet (6 comments total)

IIRC

Microsoft regards NTFS as highly proprietary, and doesn't license it out. The NTFS driver for Linux was reverse engineered, and is... not very good.
posted by Oktober at 8:05 PM on March 18

Well, I'm interested in things like write-behind caching and other known methods that may be used. I'm not so interested in linux. I want to know more about Windows and it's methods.
posted by torpark at 8:15 PM on March 18

Windows, like most modern-ish operating systems, keeps a buffer cache for filesystem access. It's not as fancy or well designed as the equivalent capability in Linux but NTFS performance is considerably better on Windows in large part because Microsoft's NTFS driver has been highly optimized over the course of many years. The bulk transfer performance difference is not really attributable to differences in caching or IO scheduling. It's probably more a matter of read/write strategy.
posted by majick at 9:38 PM on March 18

If you're using ntfs-3g then there's a whole section about why it's slow!
posted by sbutler at 9:57 PM on March 18

I followed some of the NTFS/linux debates from afar back in the day. I suspect that one of the reasons Windows performs better is that it has a lousier security model. Windows architecture privileges some key functions like memory and disk access and bypassing double-checks saves a lot of cycles -- but leaves the OS vulnerable to everybody's favorite, the buffer-overflow security loophole.
posted by dhartung at 11:11 PM on March 18

There's always wikipedia.
posted by sophist at 11:53 PM on March 18