Microsoft – OS – File System Drivers
Reviewing System Performance issues and having to dig in a bit deeper into the OS.
And, so here I am again looking for for “File System Drivers”. Funny, you should ask what are file system drivers. Well they are those “pesky” little things that sit between the OS and the File System.
The list includes:
- File Encryption
Any and everything that intercepts calls by the OS to the File System.
So googled for it and thankfully came across fltmc. fltmc is a Microsoft tool and it is bundled with our OS, Microsoft Windows 2008/R2.
The output reveals 4 columns:
- The filter name
- The number of instances in which it is loaded
- The altitude for which further information is available @ Load Order Groups and Altitudes for Minifilter Drivers (Windows Drivers) – http://msdn.microsoft.com/en-us/library/windows/hardware/ff549689(v=vs.85).aspx
Further research per each Filter yielded:
- eeCtrl –> Symantec / Anti-virus
- SRTSP –> Symantec / Anti-virus – AutoProtect
- luafv –> Microsoft (UAC File Virtualization)
- FileInfo –> Microsoft
Had a hard time determining the legitimacy of FileInfo. So launch regedit and searched for FileInfo.
From its registry anchor, here are some particulars:
- The service name is known as FileInfo
- Legacy driver (Legacy marked 1)
- It is located in %SYSTEMROOT%\system32\drivers\fileinfo.sys
More regedit search reveals:
- DependOnService –> fltmgr
- Start –> 3
- Type –> 2
In nutshell, you want to look at the list of File System Drivers and Filters. Compare that list against systems that are working a bit better. And, hopefully discover something amiss.
Or launch other system profiling tools such as xperf and try to see if any of the noted filters is a bit expensive. More on that later…
- Who scraped over my disk
References – Filter (Technical Perspective)
- Load Order Groups and Altitudes for Minifilter Drivers (Windows Drivers)
References – Filter –> luafv ( Microsoft [UAC File Virtualization])
- The deal with luafv sys
References – Filter —> Troubleshooting
- Troubleshooting Incompatible File Driver Errors
References – Microsoft – SQL Server
- Recommendations and guidelines for improving Microsoft SQL Server Performance
References – Filter —> FileInfo
- An updated system is a happy system
- Possible issues with File System Filters – FileInfo & Symantec
References – Device Manager
- Find Missing components and devices
References – Device Manager (Alternate)
References – Device Manager – Management
- How to Disable the CtxAltStr.Sys Driver
References – Device Management – Command Line
- Get a complete list of drivers on your machine