Performance, Performance, Performance

What s in Store Performance Performance Performance | Wood TV Stand

What s in Store Performance Performance Performance | Wood TV Stand — Mon, 01 Jun 2009 03:10:57 GMT

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re: Performance, Performance, Performance

Daniel A. Kornev [MSP] — Sun, 05 Feb 2006 01:36:48 GMT

Hello,

I'm developing a custom Windows Shell Namespace Extension for WinFS. It places in My Computer folder under the "Contacts" name. The reason is to provide me for the future some GUI and API to work more easily with my contacts stored in WinFS Store. The problem is that such excellent thing as Project method to retrieve custom data from selected container from WinFS works very slowly. I work with about 300 of sample contacts records and Windows Explorer slows for about 1,5 min while loading them all into the folder view. What are the ways to make perfomance of this command actually great?

I'm retrieving only DisplayName, ContactCards.EAddresses, ItemIds and that is all. What shall I do to get them faster?

Thanks,
Daniel A. Kornev,
Microsoft Student Partner.

re: Performance, Performance, Performance

Ian Thomas — Tue, 25 Oct 2005 11:53:43 GMT

NTFS filestreams are of great interest to me, since I've used the "alternate data stream" to attach metadata descriptions to some files (used in GIS - geographic info systems) so that the metadata don't get "lost". Of course, they will get lost if the user copies the 'parent' file to a non-NTFS volume or to a CD or DVD, but NTBackup handles them appropiately.
My concern has been the tendency for some anti-virus software to search out ADS (they call them "hidden streams") because they've been used occasionally by rojan / virus / malware writers.
So, my questions:
What is the detail of the special ACLs used by WinFS (and where can I find a good technical description)?
And what guarantees that anti-virus / anti-spyware software doesn't interfere with the WinFS streams that we're talking about here?

re: Performance, Performance, Performance

Tony Voellm — Thu, 13 Oct 2005 09:08:11 GMT

Arian,

The term NTFS Streams was used but the File Data is actually stored in NTFS files. NTFS does support multiple "streams" per file but few applications use it. Generally the default stream (0) is the only one used. In WinFS we dont do anything special here other than storing the data in a file that has special ACLs to keep most users from finding it and being able to modify it.

Tony

re: Performance, Performance, Performance

Arian Kulp — Sat, 01 Oct 2005 19:53:50 GMT

Thanks for your response! Actually, it didn't completely answer my question (though it was insightful nonetheless!). I can understand why file-backed items are not stored in the relational DB itself, but I'm wondering why in streams vs. NTFS files. Are streams more performant, or is it just to effectively shield those files from users to prevent problems?

Thanks!

re: Performance, Performance, Performance

Tony Voellm — Wed, 28 Sep 2005 22:22:47 GMT

Arian,

WinFS files streams are stored in NTFS to reduce the storage and retrieval overhead. Image trying to store a 2GB movie in a conventional database - there is a lot of data page encoding and transformation that occurs. Once a file in WinFS is opened the Read / Write path is essentially the same as NTFS which means there is almost no perf hit.

Some questions that come up are should icons be file backed items or native WinFS items? How about documents? There are definitely trade offs and it will depend on how the user will use your application.

The advantage of putting files in WinFS is the ability to leverage our Search, Sync and Query API's.

Tony

re: Performance, Performance, Performance

Arian Kulp — Mon, 26 Sep 2005 05:01:25 GMT

I have a performance question: In one of the PDC sessions it was mentioned that underlying files placed in WinFS are actually stored in NTFS streams. I was wondering if this was mostly a simple method of obfuscation (since most users will still access their non-WinFS folders directly), or if there was a performance benefit to storing the data this way.

Thanks!