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Where to start...
I am not exactly sure what you are trying to achieve, and I take it you assembled this code from examples, or copied it as is.
So let's start from the beginning. If you suspect that this code has errors, the first thing you should do is put all the code inside the sub into a try catch clause:
Private Sub OperateExcel()
Try
'the rest of the code here'
Catch ex as Exception
MsgBox(ex.tostring)
End Try
End Sub
Then at least you'll find out if this code works at all. After that comes the important part, comparing what this code does to what you want it to do.
A simple way to start is to write comments into the code. One comment for each step, and then fill in the code bits doing each step.
My advice is free, and you may get what you paid for.
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Hi,Johan,thanks for your suggestion.I apologize for the late reply...I used try catch clause in my code and then it told me an exception like this:
system.runtime.interop services.COMException(0x80020003):member not found.
it comes from:xlssheet = xlsworkbook.worksheet(1)
Could you give me suggestions to solve it?Thank you 
modified on Saturday, May 8, 2010 9:35 PM
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Hi sanyexian,
I changed your code a little bit so that it works. Still you might encounter many traps, since communication with Excel (i.e. COM / Office) can be very tricky sometimes. Also don't forget the small things, like making your assembly COM visible (project properties). You'll find tons of material about the issue here and in the web - and a lot is worth reading. Good luck 
Sub OperateExcel()
' Compile with Option Strict Off to allow late binding.
Dim xlsApp As Object
Dim xlsBook As Object
Dim xlsSheet As Object
xlsApp = CreateObject("Excel.Application")
' Late bind an instance of an Excel workbook.
xlsBook = xlsApp.Workbooks.Add
' Late bind an instance of an Excel worksheet.
xlsSheet = xlsBook.Worksheets(1)
xlsSheet.Activate()
' Show the application.
xlsSheet.Application.Visible = True
For Each xlsSheet In xlsBook.worksheets
' put your text into the cells in a simpler way
xlsSheet.Range("H3").Value = "txtProduct"
xlsSheet.Range("H4").Value = "txtName"
xlsSheet.Range("H5").Value = "txtNum"
' A more useful way since you can iterate through rows/colums
' Here: Place some text in the second row of the sheet.
xlsSheet.Cells(2, 8) = "This is column H row 2"
Next
xlsBook.SaveAs("D:\text.xls")
xlsBook.Close()
xlsApp.Quit()
xlsSheet = Nothing
xlsBook = Nothing
xlsApp = Nothing
End Sub
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How did that saying go again, about giving a man a fish...?
My advice is free, and you may get what you paid for.
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You're surely right on one side. On the other side I've experienced so many other traps communicating with Office (and still do, as you know from my own thread ), that he will have to dig deeper for himself anyway. Probaly he even gets more motivated by having an easier start 
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Hi,Michael.I apologize for the late reply.Thanks for your suggestion.Now I could open a Excel file,but there is an error stoped me going on.
xlsSheet = xlsBook.Worksheets(1)
I watched "xlsSheet",it display that its value was "nothing" and VS told me " HRESULT:0x80020003 (DISP_E_MEMBERNOTFOUND))"
I don't know why it happened...the file had been opened ,but why it could not get its worksheet?
Plzzz help me ,thank you!
modified on Saturday, May 8, 2010 9:34 PM
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Hi Sanyexian,
you can try xlsSheet = xlsBook.Worksheets.Add to add a new worksheet instead of referring the first available sheet with "1" (as suggested: play with IntelliSense!). The code is very basic anyway, you will need to catch exceptions (Try... Catch) and much more. You might also want to download some samples from the web and learn from them - as I wrote COM-Interaction can be tricky.
Good luck!
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I have a little tool that I use in my job for running scripts on remote machines and gathering information. Currently I'm doing this through the process class and plink/SSH which works ok. My company is looking at doing away with the SSH server on the boxes which leaves me looking for another method. I know there is psexec which might work although by default most ports are blocked by the firewall, so not positive. Is there any way I can do it programatically without the need to involve an additional application? Any method I use I need to be able to capture the output as the majority of scripts are for gathering information without logging into the server. Any help would be appreciated.
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A simple alternative that I use for this kind of thing, is ftp. Obviously this requires an ftp server that you can upload things to from anywhere.
Its pretty straightforward, but I don't think it works with sftp.
Private Sub FTP_PutFile(ByVal DestinationFileName As String, ByVal SourceFileName As String, ByVal usr As String, ByVal pwd As String)
Dim brwsr As New System.Net.WebClient
Dim creds As New System.Net.NetworkCredential(usr, pwd)
Try
With brwsr
.Credentials = creds
Console.WriteLine("Uploading file...")
.UploadFile(DestinationFileName, SourceFileName)
Console.WriteLine("Upload successful.")
.Dispose()
End With
Catch ex As Exception
EC(ex)
End Try
End Sub
Example use:
FTP_PutFile("ftp://server.address.or.ip/file.extension", "c:\temp\file.extension", "user", "password")
Just replace the .UploadFile bit with .DownloadFile(SourceFileName, DestinationFileName) when you want to download the file from the server.
My advice is free, and you may get what you paid for.
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I don't have any problems with getting files there as I have a network share that is accessible from all machines. I need a way to actually run the file or process on the remote machine though and capture the output of that file/process.
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Sorry about that, I misunderstood the question. I am afraid I can't help you with this.
My advice is free, and you may get what you paid for.
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I know the name of Domain on NT platform "MY_Domain_name".
I know the username "OU458778".
Is possibile to know the complete name of username????
With vb6, please.
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What do you mean by complete name? Like My_Domain_name\OU458778 or just the user's name like John Smith?
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yes! just the user's name like John Smith
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strUserID = InputBox("Please enter the User ID you wish to find")
strComputer = "."
Set objWMIService = GetObject("winmgmts:\\" & strComputer & "\root\cimv2")
Set objAccountColl = objWMIService.ExecQuery("Select * from Win32_UserAccount where Name = '" & strUserID & "'")
For Each objAccount in ObjAccountColl
strValue = "AccountType: " & objAccount.AccountType & vbCrLf & _
"Caption: " & objAccount.Caption & vbCrLf & _
"Description: " & objAccount.Description & vbCrLf & _
"Disabled: " & objAccount.Disabled & vbCrLf & _
"Domain: " & objAccount.Domain & vbCrLf & _
"FullName: " & objAccount.FullName & vbCrLf & _
"InstallDate: " & objAccount.InstallDate & vbCrLf & _
"LocalAccount: " & objAccount.LocalAccount & vbCrLf & _
"Lockout: " & objAccount.Lockout & vbCrLf & _
"Name: " & objAccount.Name & vbCrLf & _
"PasswordChangeable: " & objAccount.PasswordChangeable & vbCrLf & _
"PasswordExpires: " & objAccount.PasswordExpires & vbCrLf & _
"PasswordRequired: " & objAccount.PasswordRequired & vbCrLf & _
"SID: " & objAccount.SID & vbCrLf & _
"SIDType: " & objAccount.SIDType & vbCrLf & _
"Status: " & objAccount.Status
MsgBox strValue
Exit For
Next
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ok tks for reply...
But i dont see where i insert the name of domain?
 
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Hey all!
that's really odd: I have a program that hashes files.
Until now I used 1 thread to do that.
Get all files in a folder into an array list (Dim aryFi As IO.FileInfo() = di.GetFiles("*.*"))
Then with a FOR NEXT loop I hash every file in the list and add the informations to a datatable.
Now I thought I could make this faster, using 2 threads.
So I figured it out, got it to work and it's slower than before??
I tested it:
Single thread took 33 sec to hash 1000 files.
2 threads took 49 sec to hash (another) 1000 files.
(and I made sure that there was no caching by OS)
how comes? using 2 threads I split the array in 2 parts, thread_1 from 0 to half, thread_2 from half+1 to array.count-1
I call both threads like this:
thread_1.start()
thread_2.start()
thread_1.join()
thread_2.join()
The joins are there because I store the info in 2 tables and after the threads are done I make 1 table out of them.
The only problem is, why does hashing take more time than single-threaded?
The program doesn't use much cpu ressources, 2-5% only (single thread version uses 3-6%), so there's plenty of free resources.
Can anyone explain or help?
edit:
The "best" thing is, the table later contains NOT the same information as singlethreaded table does ...
the hashed files count is the same using 1 or 2 threads (resulting datatable has the same amount of rows), but the hash info seems different ...
I compare the hashes of each file with stored hashes in a 2nd database.
For example: Using the hashtable of the single-thread version gets me 240 hits.
Using the hashtable made using 2 threads gets me 222-235 hits, that number varies each time I restart the procedure ...
That is odd and I can't see why this happens at all ...
Thanks in advance,
Nik
modified on Thursday, May 6, 2010 11:54 AM
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This is not uncommon. Adding one or a few threads is fine when the operation is compute-bound and you have a multi-core, so a single thread would leave all but one cores unused. Adding threads however increases the load on all subsystems (disk, main memory, cache memory, buses, ...) and adds a small overhead too, as you now need more stacks, some synchronization, and of course some thread switching. So it is conceivable you just go from one bottleneck to another, and while doing so, the cache efficiency may go down (a phenomenon known as 'cache trashing').
I just performed a little Parallel.For experiment myself the other day, and, while I must admit it was very I/O bound, it ran 5 times slower on a dual-core than the straightforward single-thread implementation.
However switching from 1 to 2 threads, I would not expect calculating file hashes would actually slow down, well not on a normal system, with a typical disk (I am assuming your files are on a local disk, not a network disk, not a USB stick). So there always is the possibility you did something wrong, maybe you are forcing a synchronization somehow, I would need to see the code to tell for sure.
Some implementation questions would be:
are you reading the entire file to memory, or are you streaming the data?
are you using new buffers all the time, or reusing them?
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thanks for replying 
Now I have a little problem. I never learned VB.net, (somehow I even wonder how I was able to write a program like that, lol) I browsed the www and looked for the infos I need, experimented with code snippets and everything works like a charm, except the current problem where I want to make it a bit faster using 2 threads.
I updated the start post before I saw your reply.
My computer's a quadcore/iQ6600.
While the 2 threads are working (even if it's the single-thread methode) my hdd-LED doesn't flash much, I mean it's only flickering now and then, so I guess it doesn't put much load on the hdd.
hm I hope it's ok to paste the code here:
Private hashdups_m As Thread
Private hashdups_t1 As Thread
Private hashdups_t2 As Thread
Private Sub hash_folder()
Dim di As New IO.DirectoryInfo(src_cmp_fldr)
Dim aryFi As IO.FileInfo() = di.GetFiles("*.*")
If di.GetFiles("*.*").Length.ToString <> 0 Then
di_hashdups = New IO.DirectoryInfo(src_cmp_fldr)
aryFi_hashdups = di_hashdups.GetFiles("*.*")
hashdups_m = New Thread(AddressOf hashdups_main)
hashdups_m.Start()
End If
End Sub
Private Sub hashdups_main()
progb2val_a = 0
progb2val_b = 0
hashdups_t1 = New Thread(AddressOf hashdups_hash1)
hashdups_t2 = New Thread(AddressOf hashdups_hash2)
If aryFi_hashdups.Count = 1 Then
progb2val_b = 50
hashdups_t1.Start()
hashdups_t1.Join()
End If
If aryFi_hashdups.Count > 1 Then
hashdups_t1.Start()
hashdups_t2.Start()
hashdups_t1.Join()
hashdups_t2.Join()
End If
If hashdups_t1.IsAlive = False And hashdups_t2.IsAlive = False Then
ds_db_cmp_fldr.Tables.Add("db_cmp_fldr")
dt_db_cmp_fldr = ds_db_cmp_fldr.Tables("db_cmp_fldr")
Dim col_fs_dec As DataColumn = New DataColumn("filesize")
col_fs_dec.DataType = System.Type.GetType("System.Decimal")
dt_db_cmp_fldr.Columns.Add(col_fs_dec)
Dim col_sha1_string As DataColumn = New DataColumn("sha256hash")
col_sha1_string.DataType = System.Type.GetType("System.String")
dt_db_cmp_fldr.Columns.Add(col_sha1_string)
Dim col_fn_string As DataColumn = New DataColumn("filename")
col_fn_string.DataType = System.Type.GetType("System.String")
dt_db_cmp_fldr.Columns.Add(col_fn_string)
If ds_db_cmp_fldr.Tables.Contains("db_cmp_fldr_a") = True Then
For Each drSource_a As DataRow In dt_db_cmp_fldr_a.Rows
dt_db_cmp_fldr.ImportRow(drSource_a)
Next
ds_db_cmp_fldr.Tables.Remove("db_cmp_fldr_a")
End If
If ds_db_cmp_fldr.Tables.Contains("db_cmp_fldr_b") = True Then
For Each drSource_b As DataRow In dt_db_cmp_fldr_b.Rows
dt_db_cmp_fldr.ImportRow(drSource_b)
Next
ds_db_cmp_fldr.Tables.Remove("db_cmp_fldr_b")
End If
Me.Invoke(New upd_hashdups_m(AddressOf upd_hashdups_m_val), 1)
End If
End Sub
Private Sub hashdups_hash1()
ds_db_cmp_fldr.Tables.Add("db_cmp_fldr_a")
dt_db_cmp_fldr_a = ds_db_cmp_fldr.Tables("db_cmp_fldr_a")
Dim col_fs_dec_a As DataColumn = New DataColumn("filesize")
col_fs_dec_a.DataType = System.Type.GetType("System.Decimal")
dt_db_cmp_fldr_a.Columns.Add(col_fs_dec_a)
Dim col_sha1_string_a As DataColumn = New DataColumn("sha256hash")
col_sha1_string_a.DataType = System.Type.GetType("System.String")
dt_db_cmp_fldr_a.Columns.Add(col_sha1_string_a)
Dim col_fn_string_a As DataColumn = New DataColumn("filename")
col_fn_string_a.DataType = System.Type.GetType("System.String")
dt_db_cmp_fldr_a.Columns.Add(col_fn_string_a)
Dim myNewRow As DataRow
Dim aryficnt_a As Integer = Math.Ceiling(aryFi_hashdups.Count / 2)
For r1 = 0 To aryficnt_a - 1
result = Nothing
hashclass.HashFile(aryFi_hashdups(r1).FullName)
myNewRow = dt_db_cmp_fldr_a.NewRow()
myNewRow("filesize") = aryFi_hashdups(r1).Length
myNewRow("sha256hash") = result
myNewRow("filename") = aryFi_hashdups(r1).Name
dt_db_cmp_fldr_a.Rows.Add(myNewRow)
progb2val_a = (50 * (r1 + 1) / aryficnt_a)
Me.Invoke(New upd_progbar2_hash(AddressOf progbar2_val_hash), Convert.ToString(0))
Next
Me.Invoke(New upd_progbar2_hash(AddressOf progbar2_val_hash), Convert.ToString(0))
End Sub
Private Sub hashdups_hash2()
ds_db_cmp_fldr.Tables.Add("db_cmp_fldr_b")
dt_db_cmp_fldr_b = ds_db_cmp_fldr.Tables("db_cmp_fldr_b")
Dim col_fs_dec_b As DataColumn = New DataColumn("filesize")
col_fs_dec_b.DataType = System.Type.GetType("System.Decimal")
dt_db_cmp_fldr_b.Columns.Add(col_fs_dec_b)
Dim col_sha1_string_b As DataColumn = New DataColumn("sha256hash")
col_sha1_string_b.DataType = System.Type.GetType("System.String")
dt_db_cmp_fldr_b.Columns.Add(col_sha1_string_b)
Dim col_fn_string_b As DataColumn = New DataColumn("filename")
col_fn_string_b.DataType = System.Type.GetType("System.String")
dt_db_cmp_fldr_b.Columns.Add(col_fn_string_b)
Dim myNewRow As DataRow
Dim aryficnt_b As Integer = Math.Ceiling(aryFi_hashdups.Count / 2)
For r2 = aryficnt_b To aryFi_hashdups.Count - 1
result = Nothing
hashclass.HashFile(aryFi_hashdups(r2).FullName)
myNewRow = dt_db_cmp_fldr_b.NewRow()
myNewRow("filesize") = aryFi_hashdups(r2).Length
myNewRow("sha256hash") = result
myNewRow("filename") = aryFi_hashdups(r2).Name
dt_db_cmp_fldr_b.Rows.Add(myNewRow)
progb2val_b = (50 * (r2 - aryficnt_b + 1) / aryficnt_b)
Me.Invoke(New upd_progbar2_hash(AddressOf progbar2_val_hash), Convert.ToString(0))
Next
Me.Invoke(New upd_progbar2_hash(AddressOf progbar2_val_hash), Convert.ToString(0))
End Sub
the hashclass:
Public Class hashclass
Public Shared Function HashFile(ByVal File As String) As String
Dim FN As New FileStream(File, FileMode.Open, FileAccess.Read, FileShare.Read, 8192)
Dim HashValue(0) As Byte
Dim Tmp As String = ""
Dim SHA256 As New SHA256Managed
SHA256.ComputeHash(FN)
HashValue = SHA256.Hash
FN.Close()
For i As Integer = 0 To HashValue.Length - 1
Tmp = Hex(HashValue(i))
If Len(Tmp) = 1 Then Tmp = "0" & Tmp
result += Tmp
Next
Return result
End Function
End Class
Maybe there's an easier way than I found, but it works 
The single thread version nearly looks the same, it skips making 2 tables and later reading both into a new table. Also the FOR NEXT loop is just from 0 to aryFi_hashdups.Count - 1
I just don't see why it varies like I wrote in the startpost.
If you need any other infos, please ask
Thanks,
Nik
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Hi Nik,
I'm sorry to say but that code is rather horrible. I haven't studied it all, however here are first comments:
1.
there is way too much code; from your description, I would estimate the hashing should take no more than 20 lines of code.
2.
please check how often you call GetFiles(). You really need only one of those; calling it more than once wastes a lot of cycles and bytes, and does not guarantee all results will be identical, as your file system is a live object itself.
3.
you really should separate the functionality (calculate hash on a number of files) from other issues, such as the way you want to store things (DataTable).
4.
IIRC you did not mention progress bars before; they are the first suspect for the slowness. You did use Invoke (which you must), however this causes two thread switches (to the GUI thread and back), slowing down everything by a large factor.
This is how I would do this (initial approach):
1. create a little class "Result" holding filename, filesize, hashvalue
2. create a class "Job", holding a List of strings for filenames, a List of Results, and some code.
Necessary code would be:
2a. a Launch method that creates a thread which starts enumerating filenames (from its own input List), and produces results (in its own List of Results)
2b. a Join method that waits for termination, using the Thread.Join method.
3. in the main code:
3a. create N Job instances (assume N is 1 or 2) and keep them in a List of Job
3b. get a collection of all the files, and distribute them over the List of filenames in all the jobs
3c. launch the jobs
3d. wait on all jobs done
3e. go collect the results of all the jobs and post-process them
If you want progrss indication:
- give each Job a filesDone counter;
- add a System.Windows.Forms.Timer with Interval=100 that enumerates all jobs, totalizes their filesDone value, and sets that as the ProgressBar,Value (where ProgressBar.Maximum was set to the number of files returned by the initial GetFiles)
I know, all the above really says is: throw away what you have; start all over, and keep things as clean as possible.
Good luck!
PS: the above "first approach" is not optimal; there are a couple of ways to improve it, but it would be quite good if you tried it like that before going for gold.
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Hey Luc,
thanks, long reply
to be honest, it made me dizzy, right now I have no idea where to start or how to do it ...
I have to look into it and google some more ...
and you're right, there's one getfiles that can be removed because it's unused and one that I can replace by the 2nd one. I didn't notice that yet.
though the files in the folder (and the file count) won't change unless I change them manually.
I didn't think of the progressbar, I thought since I use invoke and due to my missing knowledge that it won't take time away.
So for now I'll start with trying to implement the timer instead of using invoke
Nik
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good.
if you just remove the progress stuff for now, you can judge how much it did affect the overall speed.
then, add proper progress reporting; when done right, it should not influence speed at all.
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NikWing wrote: result = Nothing hashclass.HashFile(aryFi_hashdups(r2).FullName)
myNewRow = dt_db_cmp_fldr_b.NewRow()
myNewRow("filesize") = aryFi_hashdups(r2).Length
myNewRow("sha256hash") = result
I had a closer look at this part of your code; how is result getting its value here?
HashFile is a method that returns "result" but the caller is not storing it at all?
And inside HashFile the variable result is not declared and not initialized. This is all wrong.
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Thanks for your time, Luc
no no, I just didn't paste the code you're missing
the program is about 4200 lines right now so I kinda forgot to paste this:
Public Module Variables_form1
Friend result As String = ""
End Module
so I set result to nothing, call the hashfile function with the full filename, it returns the hash and stores it in a new datatable row
like I said, the original program runs without a flaw, just the double-thread stuff breaks it somehow ...
I gave up for today 10 mins ago.
the timer instead of invoke didn't speed it up.
the progressbar value is between 96% and 100%, usually 99%.
progbar.Maximum value is aryFi_hashdups.count, current value is the sum of each FOR .. NEXT counter, ((r1) + (r2 - aryficnt_b + 1)) where aryficnt_b = Math.Ceiling(aryFi_hashdups.Count / 2)
But beside this, the tables are broken somehow
I thought the problem occurs when I copy each table row by row to a new table
but both have the correct amount of lines, as in, I hashed 838 files, each table contains 419 rows
I skipped making a new table out of table_a and table_b and altered the compare part to use table_a, then table_b.
the problem still occurs, the number of results varies. I tried it with my single thread version, the result won't vary and it's correct.
I now try to find out if the aryFi_hashdups array varies. I can't imagine this, why should it alter itself while the program runs? it's just a list of filenames as far as I know (di.getfiles(*.*), and after it's created nothing changes it ...)
I divide it's count by 2, round one to floor, one to ceiling and have 2 loops
Dim aryficnt_a As Integer = Math.Floor(aryFi_hashdups.Count / 2)
For r1 = 0 To aryficnt_a - 1
Next
and
Dim aryficnt_b As Integer = Math.Ceiling(aryFi_hashdups.Count / 2)
For r2 = aryficnt_b To aryFi_hashdups.Count - 1
Next
I just don't understand, I don't see anything that interferes ...
edit: uh, just thought of something ... could the problem be that I only have one hash function and also just one "result" ?
I'll copy the hash function and change result to result_a and result_b and see if that works ...
I will try that now, though it's already 1:25 am ^^
edit2: I guess that was the problem of the wrong results. now the result won't vary anymore. I also fixed the progressbar value, I have to make more tests with different files, but for now it finishes with 100%
with taskman I monitored the cpu usage. without visible caching (1st run) it uses between 2 and 5% of CPU, no idea why it doesn't use more. the hdd isn't very active, only flashing now and then.
WITH visible caching (2nd run etc) it uses 50% of the CPU and of course is much faster.
I have to compare both versions of the code again, how much time each takes for 1000 files and if anything improved ...
modified on Thursday, May 6, 2010 7:32 PM
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NikWing wrote: Public Module Variables_form1
Friend result As String = "" End Module
OK, that is completely wrong and would explain why some of the hash values are off. You only have one "result" variable, yet two threads are writing to it and reading from it. So the order of operations will be determined by chance, and at some point in time it could be:
thread1 writes 111
thread2 writes 222
thread2 reads, hence gets 222
thread1 reads, hence gets 222 instead of 111
furthermore, while executing, the HashFile function constantly changes "result". So it is almost by accident that some of your hashes end up being correct!
Your HashFile function returns the result, no need to use an external variable at all. Here is what you do:
remove Friend result As String = ""
add a result variable inside HashFile
where you call HashFile, do it like so: Dim result as Long=...HashFile...
so now each thread receives the correct value and stores it locally.
Haven't read most of your message yet. May have more to comment later.
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