disk

Disk partition structure

Hi, Is there any way in Java (1.6+) to retrieve the partition disk structure? (For example: NTFS, FAT32, HFS+, or EXT3.) External libraries are permitted. Thanks, Gianni ...

save on cost when using Amazon EBS

Seeing that Amazon has priced the usage of EBS as: $0.10 per GB-month of provisioned storage; $0.10 per 1 million I/O requests Even though the value is in millions, I/O request add up pretty quickly ... I was wondering if there are any best practices for reducing I/O requests out there. E.g. Use an instance with more than enoug...

Writing a file quite quick, overwriting the file take much longer...

I have been seeing a few performance problems with a PHP script on a Linux Fedora Core 11 box, so I was running some commands to look for a bottleneck. One thing I noticed was that writing a file is pretty quick: [root@localhost ~]# dd if=/dev/zero of=/root/myGfile bs=1024K count=1000 1000+0 records in 1000+0 records out 1048576000 byte...

Determine available disk size with a sql query

I need to determine the available space on the drive where my database lives. I know about the xp_fixeddrives procedure but how do I get the info for the specific drive where my database resides? ...

MySQL innodb seeks vs. contiguous reads tradeoff

Would mysql (innodb) support a higher rate (queries per second) of queries like (A) or (B)? (A) SELECT * FROM t1 WHERE pkey BETWEEN 2000 and 2001 AND x > 300 In (A), the primary key selects a range of 800 rows. "x" is unindexed. there's one range lookup and 1 contiguous read of length 200kb. (B) (SELECT * FROM t1 WHERE pkey BETWEEN 20...

Does disk caching with NSURLRequest and NSURLConnection actually work on the iPhone?

I have a UITableView whose cells contain custom ImageViews that asynchronously load the images from the internet. To load those images I use NSURLRequest and NSURLConnection which works fine. The only problem is that the images are not cached and therefore are downloaded every time they are used. I tried to set the cachePolicy of the NSU...

sequential vs. binary search

Consider a file on disk containing 100 records. For both searches, what is the average number of comparisons needed to find a record in a file. number of comparisons if the record is not in the file the average number of comparisons if the record has a 68% chance of being in the file the number of disk accesses in the previous 3 quest...

what the best and simplest way to find out whether a volume need defrag?

I am writing a application that monitor the system's health, user should know when they need to defrag the volumes. What I am thinking is calling the "defrag.exe /A" then analyze the output result to see whether it contains "You do not need to defragment this volume." But it's slow and very bad, I fount that the "Analyze" is really qui...

How can I write a folder of WPF image resources to disk?

I have a folder in my WPF app "Images" that has several .png files with their Build Action set to Resource. These are built into my binary since I can reference them in XAML. I would like to write these to disk in the temp folder. How do I do this? I have found several answers referring to Embedded Resources, but not just plain resourc...

How many files can i have opened at once?

On a typical OS how many files can i have opened at once using standard C disc IO? I tried to read some constant that should tell it, but on Windows XP 32 bit that was a measly 20 or something. It seemed to work fine with over 30 though, but i haven't tested it extensively. I need about 400 files opened at once at max, so if most moder...

Is there any way to get a list of connected servers in OS X? (Bash, Obj C, AppleScript...)

Simply, I'm just looking to get a list of connected remote disks. I have a script right now that compares /Volumes/ to "diskutil -list" but that only gives me the name of the remote disks, not the actual address. Anyone have ideas as to how I might go about doing this? Thanks in advance. ...

Which is the fastest way to scan files in FAT32 disk?

I want to scan FAT32 disk (I just need file path and file name) as soon as possible in C++, Scan every files on FAT32 disk. Is there any API to do this? Many thanks! ...

Need data on disk drive management by OS: getting base I/O unit size, “sync” option, Direct Memory Access

Hello All, I want to ensure I have done all I can to configure a system's disks for serious database use. The three areas I know of (any others?) to be concerned about are: I/O size: the database engine and disk's native size should either match, or the database's native I/O size should be a multiple of the disk's native I/O size. Dis...

Which Qt classes use the disk directly?

I'm trying to write a library to separate all the disk activity out into its own thread, but the documentation doesn't really care about such things. What I want to accomplish is that aside from startup, all disk activity is asynchronous, and for that, I need to wrap every class that accesses the disk. Here's what I found so far: QtCor...

How can I monitor disk access for a certain file?

I want to use performance monitors to determine when a file is being accessed (read/write). Is this possible? If not, is there any other way? My OS is Windows Server 2008 R2, and I am writing the code in C#. ...

How can I get identity of a disk?

I want to identify disk in c++ in my windows application. For example: I have a disk on E:\ Then I changed the disk, and replace it with another one. the name is still E:\ How can I know the disk is changed, it is not the original one? If I have no administrator priority in win7, Can I still use some method to identy different disks? ...

Automating Disk Cleanup on Windows using commands

Hi, I asked this question on MSDN forum but there was no response.. Maybe I had posted in the wrong forum... So I'm posting it again here, hoping that someone might be able to help me out here... I am trying to run Disk Cleanup in the command prompt (and through a C# program) and so I went through all the available options from this li...

Does GetVolumeNameForVolumeMountPoint() return the GUID of a volume?

Does GetVolumeNameForVolumeMountPoint() return the GUID of a volume in c++? GetVolumeNameForVolumeMmountPoint() { LPCTSTR lpszvolumeMountPoint, LPTSTR lpszVolumeName, DWORDcchBufferLength, } I mean if I am using a removeable disk. will the lpszVolumeName remained the same on the same computer? Does it return a certain ID for a certain...

Is There any API in windows to detect whether the disk situation is changed?

I am writting a application to detect the change of system disks. for example, if user insert a disk, the application can detect this event. If user change the volume label, I can receive the message. Is there any APIs to detect this kind of event? Many Thanks! ...

Disk IO Performance Limitations based on numbers of folders/files

I have an application where users are allowed to upload images to the server. Our Web Server is a windows 2008 server and we have a site (images.mysite.com) that points to a shared drive on a unix box. The code used to do the uploading is C# 3.5. The system currently supports a workflow where after a threshold is met a new subfolder c...