我正在使用文件流写入文件,并使用
Process Monitor
. 在生产部署中,我遇到了一些文件锁定问题,因此我将密切关注细节。
此示例代码:
using (FileStream fs = new FileStream("c:\\temp\\test.txt", FileMode.Create, FileAccess.Write, FileShare.Read))
{
fs.Write(new byte[] { 1, 2, 3, 4, 5 }, 0, 5);
fs.Close();
}
导致以下系统调用:
9:27:09.4561092 AM ConsoleApplication1.vshost.exe 2320 CreateFile C:\temp\test.txt SUCCESS Desired Access: Generic Read/Write, Disposition: OverwriteIf, Options: Synchronous IO Non-Alert, Non-Directory File, Open No Recall, Attributes: n/a, ShareMode: Read, AllocationSize: 0, OpenResult: Overwritten
9:27:12.2217409 AM ConsoleApplication1.vshost.exe 2320 WriteFile C:\temp\test.txt SUCCESS Offset: 0, Length: 5
9:27:12.2219901 AM ConsoleApplication1.vshost.exe 2320 CloseFile C:\temp\test.txt SUCCESS
9:27:12.2234484 AM ConsoleApplication1.vshost.exe 2320 CreateFile C:\temp\test.txt SUCCESS Desired Access: Generic Read, Write Attributes, Disposition: Open, Options: Synchronous IO Non-Alert, Non-Directory File, Complete If Oplocked, Random Access, Attributes: N, ShareMode: Read, Write, Delete, AllocationSize: n/a, OpenResult: Opened
9:27:12.2248664 AM ConsoleApplication1.vshost.exe 2320 QueryBasicInformationFile C:\temp\test.txt SUCCESS CreationTime: 10/29/2008 9:04:14 AM, LastAccessTime: 10/29/2008 9:27:12 AM, LastWriteTime: 10/29/2008 9:27:12 AM, ChangeTime: 10/29/2008 9:27:12 AM, FileAttributes: A
9:27:12.2250075 AM ConsoleApplication1.vshost.exe 2320 SetBasicInformationFile C:\temp\test.txt SUCCESS CreationTime: -1, LastAccessTime: -1, LastWriteTime: -1, ChangeTime: -1, FileAttributes: n/a
9:27:12.2255889 AM ConsoleApplication1.vshost.exe 2320 QueryStandardInformationFile C:\temp\test.txt SUCCESS AllocationSize: 8, EndOfFile: 5, NumberOfLinks: 1, DeletePending: False, Directory: False
9:27:12.2257571 AM ConsoleApplication1.vshost.exe 2320 ReadFile C:\temp\test.txt SUCCESS Offset: 0, Length: 5
9:27:12.2259825 AM ConsoleApplication1.vshost.exe 2320 ReadFile C:\temp\test.txt SUCCESS Offset: 0, Length: 5
9:27:12.2261588 AM ConsoleApplication1.vshost.exe 2320 ReadFile C:\temp\test.txt SUCCESS Offset: 0, Length: 5
9:27:12.2265161 AM ConsoleApplication1.vshost.exe 2320 ReadFile C:\temp\test.txt SUCCESS Offset: 0, Length: 2
9:27:12.2268237 AM ConsoleApplication1.vshost.exe 2320 ReadFile C:\temp\test.txt SUCCESS Offset: 0, Length: 5
9:27:12.2271332 AM ConsoleApplication1.vshost.exe 2320 ReadFile C:\temp\test.txt SUCCESS Offset: 0, Length: 5
9:27:12.2272841 AM ConsoleApplication1.vshost.exe 2320 ReadFile C:\temp\test.txt SUCCESS Offset: 0, Length: 5
9:27:12.2274779 AM ConsoleApplication1.vshost.exe 2320 ReadFile C:\temp\test.txt SUCCESS Offset: 0, Length: 5
9:27:12.2276249 AM ConsoleApplication1.vshost.exe 2320 ReadFile C:\temp\test.txt SUCCESS Offset: 0, Length: 5
9:27:12.2278766 AM ConsoleApplication1.vshost.exe 2320 ReadFile C:\temp\test.txt SUCCESS Offset: 0, Length: 5
9:27:12.2282577 AM ConsoleApplication1.vshost.exe 2320 ReadFile C:\temp\test.txt SUCCESS Offset: 0, Length: 5
9:27:12.2284476 AM ConsoleApplication1.vshost.exe 2320 QueryFileInternalInformationFile C:\temp\test.txt SUCCESS IndexNumber: 0x2d000000016b88
9:27:12.2286183 AM ConsoleApplication1.vshost.exe 2320 CloseFile C:\temp\test.txt SUCCESS
9:27:12.2288759 AM ConsoleApplication1.vshost.exe 2320 CreateFile C:\temp\test.txt SUCCESS Desired Access: Read Attributes, Write Attributes, Disposition: Open, Options: , Attributes: n/a, ShareMode: Read, Write, Delete, AllocationSize: n/a, OpenResult: Opened
9:27:12.2305722 AM ConsoleApplication1.vshost.exe 2320 QueryBasicInformationFile C:\temp\test.txt SUCCESS CreationTime: 10/29/2008 9:04:14 AM, LastAccessTime: 10/29/2008 9:27:12 AM, LastWriteTime: 10/29/2008 9:27:12 AM, ChangeTime: 10/29/2008 9:27:12 AM, FileAttributes: A
9:27:12.2307379 AM ConsoleApplication1.vshost.exe 2320 CloseFile C:\temp\test.txt SUCCESS
前三个IO调用是预期的(create、write、close),但是这个过程继续读取文件十几次,并重复打开和关闭文件。
我现在已经在win xp sp2和win 2003 x64上观察到这种行为。但是,我在家里的WindowsVista机器的性能与预期的一样(仅前三行)。
有什么线索可以解释为什么在非Vista运行时会发生这种情况?
