Disk Defragmenter Beta Chat Transcript (July 26, 2006)

[FileCAB-Team]

First published on TECHNET on Aug 16, 2006

Chat Topic: Disk Defragmentation
Date: Wednesday, July 26, 2006



Wendy [MSFT] (Moderator):
Welcome to today’s chat with the Windows Defrag Team.  We will try to answer as many questions as we can today. Participants should type their questions, select the “Ask the experts” check box, and click “Send.” Those posts will go into a private queue, from which our experts will draft answers and repost questions in the upper window with their answers. (To confirm: if you selected the “Ask the experts” check box when you posted, you don’t need to resubmit.

At this time, I’ll let the experts introduce themselves.

Wendy [MSFT] (Moderator):
My name is Wendy and I’ll be your tour guide today.  If you look out the left window, you’ll see the Vista landscape and off to the right we’re just coming upon the Disk Defrag chat.

Sam[MSFT] (Expert):
Hello my name is Sam and I am a developer working on Defrag. Sitting with me is Victoria, a tester working on Defrag.

Defrag Team [MSFT] (Expert):
Hi I am Ivan. I am the Dev Lead for Defrag.

Hi I am Varun. I am one of the testers for Defrag.

Georgi Matev [MSFT] (Expert):
Hi everyone. My name is Georgi Matev and I'm the Program Manager for defrag in Vista.

Charles [MSFT] (Expert):
Hi all, I am Charles, one of the developers for Defrag

Defrag Team [MSFT] (Expert):
Q: Could a user lose access on some files while Vista is performing a defrag? (example, the ability to save or move a file while defrag is handling it?)
A: No you should be able to continue to use normally the files while they are defragmented

Defrag Team [MSFT] (Expert):
Q: Has the MFT % been set to change dynamically based on the drive contents?
A: The percentage of initial space reserved for MFT on the volumes has been decreased on Vista. Both on Vista and on XP the MFT can grow as needed when new files are added to the volume.

Sam[MSFT] (Expert):
Q: Is defrag supposed to be running automaticaly? and if Yes how often with each SKU?
A: Yes, defrag in Vista is scheduled to run once per week by default. This happens now at 1am every Wednesday. In previous builds it was 4am Sunday. This is the same for every SKU.

Defrag Team [MSFT] (Expert):
Q: Doses Defrag optimize on file usage?
A: Can you please clarify what you mean by "Doses Defrag optimize on file usage?"

Defrag Team [MSFT] (Expert):
Q: Have there been any changes to the reporting, or logs, generated by defrag?
A: No there are no changes in that aspect

Georgi Matev [MSFT] (Expert):
Q: Is Executive software still providing the defrag program for vista?
A: No the defrag in Vista is done by the Microsoft team.

Charles [MSFT] (Expert):
Q: Is there or will their be options for compacting (defraggin freespace) and 'wear leveling' (spreading the data across the disk)?
A: Vista Defrag will move files fragments to the front of the as part of the defragging process . This aims to consolidate free spaces at the end of the disk. There is no command line option exposed for compacting free spaces only though.

Defrag Team [MSFT] (Expert):
Q: Q: Although defrag is supposed to use low-priority I/O in Vista, are you guys actually testing this on underpowered boxes?  Believe me, people are going to run Vista on underpowered boxes by the dozen...
A: Defrag in Vista uses low priority IO, as well as low CPU and memory priority. This is tested thoroughly. Can you please clarify what do you mean by "underpowered boxes"?

Sam[MSFT] (Expert):
Q: When does my computer get defragged if it is down at 1 AM on Wednesday?
A: Next time you turn it on, defrag will run 30 minutes after starting Vista.

Georgi Matev [MSFT] (Expert):
Q: Are there plans to build a GUI for the detailed defrag status?
A: Not for Vista. There will be improvements in the defrag engine APIs which will aloow for much better reporting of status in the future. For Vista all of the defrag UI is built on top of a scheduled task and the command line.

Wendy [MSFT] (Moderator):
For those just joining us, today’s chat is about Disk Defragmentation.  To post a question, please type your question, select the “Ask the experts” check box, and click “Send.”

Sam[MSFT] (Expert):
Q: How often should the average computer user defrag their hard drives?
A: Defrag is currently scheduled to run once per week without any user input. We believe that this should suffice for the average user. Power users can schedule defrag to run more frequently if they wish.

Defrag Team [MSFT] (Expert):
Q: Will the defrag utility in Vista allow you to set a static MFT size to prevent fragmentation?
A: The size of the MFT is controlled by the file system. It grows the MFT dynamically as needed when more files are added to the volume. Restricting the size of the MFT would lead to severe problems using the volume. However Defrag does support defragmenting the MFT, except the first fragment, which is unmovable.

Georgi Matev [MSFT] (Expert):
Q: Can we please have some form of GUI to see what it's doing?  Moving little blocks satisfies that need, if even just a little.  Please let us see what's going on!
A: There will be future improvements in this area for future releases of Windows. For Vista the whole idea is to eliminate the need for users to ever run defrag explicitly. It is a process that can take a while watching it move file blocks is not really useful. When done on a schedule defrag will happen regularly and will have just little chunks of work to do each time and will be completing much faster so reporting status correctly is not crucial.

Georgi Matev [MSFT] (Expert):
A: Good question. As far as the user experience changes are concerned, the decision to simplify the user interface came as a result of usability research that we did accross various types of users (advanced to novice). The results in most cases indicated that people did not have good understanding of defragmentation and were not using it very often. Because of this we chose to simplify the UI while leaving control to advanced users in the command line. For some of the technical changes you can refer to the blog entry at https://blogs.technet.com/filecab/articles/440717.aspx

Georgi Matev [MSFT] (Expert):
Q: Can you share with us the data you have that led to the decision to change the way defrag works in Vista compared to XP?
A: Good question. As far as the user experience changes are concerned, the decision to simplify the user interface came as a result of usability research that we did accross various types of users (advanced to novice). The results in most cases indicated that people did not have good understanding of defragmentation and were not using it very often. Because of this we chose to simplify the UI while leaving control to advanced users in the command line. For some of the technical changes you can refer to the blog entry at https://blogs.technet.com/filecab/articles/440717.aspx

Georgi Matev [MSFT] (Expert):
Q: Why was the XP style Graphical User Interface dropped? (the before and after defragmentation look was a good design)
A: You can find a lot of detail about this at the Defrag FAQ http://blogs.technet.com/filecab/articles/440717.aspx

Sam[MSFT] (Expert):
Q: "power users can use a command-line tool to view detailed fragmentation  status and results". Where do I find info about it?
A: If you run defrag from the command line (defrag.exe <driveLetter>), you can use the verbose flag /v to get more detailed output.  Running defrag.exe /? will list the other options that you can use with the Command Line defrag tool.  Make sure to run from an elevated (administrator) command prompt.

Defrag Team [MSFT] (Expert):
Q: Q: Many testers reported that multiple command-line defrags of their Vista partitions made zero improvement to the reported fragmentation, and in some cases it got worse.  Have you observed this?  Why does this happen when it's not an issue in XP?
A: The Beta2 builds were had some problems properly acounting the free space in the fragmentation report. This has been improved significantly in recent builds. You should see difference in future builds.

Georgi Matev [MSFT] (Expert):
Q: Why is choosen to leave the 64 Bit chunks in place and not moved, the way defrag is working for now it's not doing the needed job, when disabled and do a defrag from XP to the Vista drive with 3erd party tools Vista responds better.
A: I assume you are refering to the partial defrag algorithm which is the default in Vista. We want to take advantage of the fact that the biggest performance gain from defragmentation is when you combine files in "big enough" extents. "Big enough" here is 64 MB, which happens to be about the extent size for which the disk-seek latency starts to become negligible compared to the latency associated with sequentially reading the extent. This means that the performance benefit of coalescing two extents larger than 64 MB is minimal while the I/O load and free space requirements are significant. The different levels of fragmentation that you see for the same volume from Windows XP and Windows Vista are a result of this different treatment of large extents.

Sam[MSFT] (Expert):
Q: a bug report was filed that showed discrepencies between what the defrag GUI said, and what the CLI defrag said (ie one said you should defrag, the other said you shouldn't). given those drastic differences in opinion why should anyone trust the defrag GUI
A: This was a bug and it has been fixed. The two should agree.

Defrag Team [MSFT] (Expert):
Q: Will Defrag adjust to not run when Low Power profiles are loaded? Because I've seen high activity from defrag when idle on battery.
A: Defrag is not designed to address such problems. It does not directly modify the on disk file system structures. You should run chkdsk /r on the volume in question. Chkdsk is the tool, which has the knowledge how fix such problems.

Georgi Matev [MSFT] (Expert):
Q: Will the final version have a display on defragment process when run from the GUI? command line options are useless for end users.
A: This will not be done for Vista but we'll be making improvements in this area in future releases when some of the interfaces for communicating with the defrag engine are improved.

Charles [MSFT] (Expert):
Q: Q: [...] was there any change in Vista to help NTFS resist fragmentation?  Have the algorithms changed at all since XP/WS2003?
A: There has been tremendous change to Defrag algorithm in Vista over WS2003 and especially over XP. In Vista, we allow defragmentation of large files under low disk space or highly fragmented free space condition. Vista defrag also attempt to consolidate free space at the end of the disk so as to allow NTFS to grow file contiguously.

Georgi Matev [MSFT] (Expert):
Q: Any chance the UI will be improved to give advanced users more control ie which drives are defragged and more information like graphical display we get in XP?
A: This will not be done for Vista but we'll be making improvements in this area in future releases when some of the interfaces for communicating with the defrag engine are improved.

Defrag Team [MSFT] (Expert):
Q: Will there be any GPO settings that can be used to schedule disk defragmention?
A: No, there are no GPO settings in Vista client. Still you can create a custom scheduled task running the defrag. Adding GPO settings is something we may consider for the incoming server release.

Wendy [MSFT] (Moderator):
For those just joining us, today’s chat is about Disk Defragmentation.  To post a question, please type your question, select the “Ask the experts” check box, and click “Send.”

Sam[MSFT] (Expert):
Q: Will Defrag adjust to not run when Low Power profiles are loaded? Because I've seen high activity from defrag when idle on battery.
A: Defrag will not start if the computer is running on batteries. It will only run on battery power if you start defrag explicitly. Also, if defrag is running and your battery becomes very low, it will quit and show a message to the user.

Georgi Matev [MSFT] (Expert):
Q: Where can we find the defrag program in vista beta 2?  can't seem to locate it in the program files
A: You can find it in Accessories -> System tools

Defrag Team [MSFT] (Expert):
Q: Will primary disk "offline" defragging be available in Vista?
A: No currently there are no plans to have such ability in Vista.

Charles [MSFT] (Expert):
Q: In what ways are the Disk Defragmentation team working on external media?
A: On external hardisk, there should be no difference as internal harddisk.

Defrag will not touch removeable media.

Georgi Matev [MSFT] (Expert):
Q: I ever wondered why the S.M.A.R.T. technology wasn’t used to preserve hard-disks’ health while defragmenting huge files, like for example VPC virtual hard-disks. Do you plan to add the S.M.A.R.T. support?
A: We do query volumes for the disk status reported by SMART and if the disk comes back as failing defrag willl not run.

Defrag Team [MSFT] (Expert):
Q: Q: If you make a CompletePC[tm] backup, replace the hard drive with anew one, and restore the backup, is the fragmentation restored as well?
A: Yes, the volume is restore block by block to exactly the same state as it was during the backup, including the file placement and fragmentation.

Sam[MSFT] (Expert):
Q: in a multi-drive system (C, D, etc) and systems with connected external USB drives -  will all of these drives be defragmented by default? or just the C drive? can that behavior be changed?
A: If you run defrag with the -c command line option (this is how it is run by default) all volumes will be defragmented. This includes local hard disks and external drives. There are command line options provided with defrag to select one specific drive to defragment.

Defrag Team [MSFT] (Expert):
Q: If defrag is set to run automagicaly at 1 am every week and you are on dial up, meaning you shut the machine down every night, how is you hdd going to get defraged???
A: The defragmenter scheduled task is created in such way that if the normal run time is missed, half an hour after the next boot it will run automatically. I don't understand how "dial up" is related to defrag though, can you please clarify with more details?

Georgi Matev [MSFT] (Expert):
Q: Have there been any improvements in the speed? If so, could you elaborate a little on how the process was sped up?
A: There are two different factors working in opposite directions here. On one hand the partial defrag algorithm allows for faster defragmentation but on the other hand defrag is doing low-priority I/O (to minimize impact on interactive use) which will cause defragmentation to take longer if there is other higher priority I/O activity.

Sam[MSFT] (Expert):
Q: Does Defrg do a "Dirty" Flag check before running ?
A: Yes it does. If it finds the "dirty" flag on a volume, it will skip that volume and recommend that the user run autochk.