On Tuesday, February 01, 2005 7:53 PM [EST], Brian Dessent wrote: > Ken Sheldon wrote: > >> Not only Cygwin apps incur this large performance penalty. >> Something similar happens with the cmd.exe prompt command "DIR", >> with the windows file explorer, or with IIS (FTP server). This >> only seems to happen in the directory structures created by my >> CygWin scripts (using apps: tar, wget, cp) > > If I had to take a wild guess I'd say that's because when a normal > win32 app creates a file it usually inherits its ACL from the parent > directory, and presumably NTFS is tuned for this in some way so that > checking thousands of such files that all inherit ACLs is fast. > However, when cygwin creates a file or dir it usually sets the > permissions explicitly to match what you would expect on a POSIX > system (i.e. 644 or 755.) Try creating your files/folders with > "nontsec" set and see if the cygwin-created trees are as slow as > native-created ones. > > Brian
NTFS in general just isn't very fast when you really start using some of the advanced features. Its just not tuned very well for large amounts of files. A perfect example of this is when you need to delete alot of files and directories all at once - it takes an awfully long time to do when compared to ext2/3 or reiserfs, and I've noticed that sometimes the system doesn't properly clean up the directory indexes, leaving stale ACL entries and such (run chkdsk, boot, do a bunch of filesystem operations such as deleting files, then run chkdsk again, and most likely, it will report even more errors). MFT fragmentation seems to compound already existing problems. -- Brian Bruns The Summit Open Source Development Group http://www.sosdg.org / http://www.ahbl.org -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/
