defragmentation

What is a good algorithm for compacting records in a blocked file?

Suppose you have a large file made up of a bunch of fixed size blocks. Each of these blocks contains some number of variable sized records. Each record must fit completely within a single block and then such records by definition are never larger than a full block. Over time, records are added to and deleted from these blocks as records ...

Windows disk partition gap

Windows XP Disk Defragmenter report shows a constant gap in disk usage on a number of disk partitions on my system. I'm not referring to the little transitory gaps that occur. In disk D below, the gap in question is the one under the word "defragmentation". In disk P below, the gap is the one under "usage before def" the but a bigge...

Should I drop and create indexes on my tables that SQL Server created?

In an effort to get rid of some fragmentation left from rebuilding and defraging we thought that we would drop and create indexes so I went to write a script. It identifies a clustered index that needs work and drops indexes and primary keys and rebuilds the indexes and primary keys for a table. Here is the problem I ran into: SQL Serv...

C++ Memory Management for Texture Streaming in Videogames

Hi, this is a "hard" question. I've found nothing interesting over the web. I'm developing a Memory Management module for my company. We develop games for next-gen consoles (Xbox 360, PS3 and PC... we consider PC a console!). We'll need in future, for our next games, to handle texture streaming for large game worlds that cannot be load...

Move OS files to the begin of the disk

I would like to know if it's possible to move the files on a given partition to the begin of the disk, where the read/writes are faster. I currently have Windows Vista installed on the first partition of the disk with a few more partitions for work related files and other stuff. Would this guarantee that the OS partition (which was th...

Mysql OPTIMIZE TABLE for all fragmented tables

Id like to run optimize on all currently framgmented tables. These tables should be those that have information_schema.DATA_FREE > 0. Is it possible to optimize all tables with this property in one command in sql or will I have to write external code to do this? ...

Logic in Disk Defragmantation & Disk Check

What is the logic behind disk defragmentation and Disk Check in Windows? Can I do it using C# coding? ...

Defragmenting C++ Heap Allocator & STL

I'm looking to write a self defragmenting memory manager whereby a simple incrementing heap allocator is used in combination with a simple compacting defragmenter. The rough scheme would be to allocate blocks starting at the lowest memory address going upwards and keeping book-keeping information starting at the highest memory address...

Defragmenting Windows Drives as part of an NSIS installer script?

I need to install a piece of software with a lot of files. Our experience showed, that on highly fragmented hard drives that leads to very poor performance. So I want to include automatic disk defragmentation into my installer (which I plan to write using NSIS). How can I include a defrag command and read the results as part of my instal...

Defragmenting SQL indexes

I have been trying to defrag indexes in SQL Server 2005 and nothing seems to work. I have created multiple Maintenance Plans using the wizard but the job always fails. I have run the script from this site, which is originally from Microsoft: http://blog.sqlauthority.com/2008/03/04/sql-server-2005-a-simple-way-to-defragment-all-indexes...

How does disk de-fragmenting work?

I'd like to have a go at writing something which shows the state of a hard drive in terms of how fragmented it is. Maybe even has a go at de-fragmenting it. But I've realised that I don't fully understand how this works. Can anyone explain this to me and perhaps offer some suggestions of where I might start? I mainly use C# - would th...

How can I find information about a file from logical cluster number in NTFS/FAT32?

I am trying to defragment a single file through Windows defragmentation API ( http://msdn.microsoft.com/en-us/library/aa363911(VS.85).aspx ) but if there is no free space block large enough for my file I would like to move other parts of files to make room for it. The linked article mentions moving parts of other files but I can't find ...

Programatically determine a file's fragmentation status

Is it possible to determine a specific file's fragmentation status (that is, the amount of distinct fragments this file occupies)? If so, how can this be done using .net? The motivation is this: my application is keeping data in a FileStream, changing its size on-demand. This eventually causes the file to be fragmented. I'd like to mon...

Is defragging tough on replication?

I've been told that defragging causes the log to grow tremendously. Is this true? If so, is there something better to do than defragging that will not impact the log as much? We are running SQL Server 2005 replicating between 2 sites. ...

Reconstructing data from PCAP sniff

Hi everyone !! I am trying to sniff HTTP data through libpcap and get all the http contents (header+payload) after processing the TCP payload. As per my discussion at http://stackoverflow.com/questions/2905430/writing-an-http-sniffer-or-any-other-application-level-sniffer , I am facing problems due to fragmentation - I need to reconstr...

Windows cannot initialize a synchronization event

I get the above error message in a Windows batch file that tries to defrag two disks (Windows XP Professional SP3), on the second defrag. The first one works fine. The relevant code is: echo My C: defrag started: %date% %time% > %logfile% defrag C: /v 1>> %logfile% 2>&1 echo My C: defrag finished: %date% %time% >> %logfile% echo My E: d...