Release 1.0

Author: extratype

README.md

@@ -46,7 +46,7 @@ I'm not responsible for the data stored using chunkdisk!
 ## Issues
 
 * winspd-x64.dll is not compatible with the original to workaround [an issue](https://github.com/billziss-gh/winspd/issues/10). Specifically, invoking `SpdStorageUnitSendResponse()` or `SpdIoctlTransact()` leads to an undefined behavior. It's fine with the current WinSpd binaries though. The source code is available [here](https://github.com/extratype/winspd).
-* I/O performance is not great with SSDs.
+* Random I/O performance is not great with SSDs.
 
 ## Notes and Tips
 

chunkdisk.rc

@@ -1,8 +1,8 @@
 #include <winver.h>
 
 VS_VERSION_INFO VERSIONINFO
- FILEVERSION 0,9,0,0
- PRODUCTVERSION 0,9,0,0
+ FILEVERSION 1,0,0,0
+ PRODUCTVERSION 1,0,0,0
  FILEFLAGSMASK 0x3fL
 #ifdef _DEBUG
  FILEFLAGS 0x1L
@@ -18,12 +18,12 @@ BEGIN
         BLOCK "040904b0"
         BEGIN
             VALUE "FileDescription", "chunkdisk"
-            VALUE "FileVersion", "0.9.0.0"
+            VALUE "FileVersion", "1.0.0.0"
             VALUE "InternalName", "chunkdisk.exe"
             VALUE "LegalCopyright", "Copyright (C) 2021 extratype"
             VALUE "OriginalFilename", "chunkdisk.exe"
             VALUE "ProductName", "chunkdisk"
-            VALUE "ProductVersion", "0.9.0.0"
+            VALUE "ProductVersion", "1.0.0.0"
         END
     END
     BLOCK "VarFileInfo"

docs/archived.txt

@@ -46,3 +46,16 @@ Performance experiments with DiskSpd:
     DRAM: > 1M IOPS, so single dispatcher
     SSD: parallel accesses > outstanding (queued) accesses
     HDD: better sequential performance with queue, tune total request size
+
+WinSpd requests while sequential access:
+    Split in maximum transfer length
+
+    Overlap requests in multiple threads to keep disk busy
+        Buffered read: 2 ~ 4 threads
+        Buffered write: up to 5 threads
+
+    Requests more out of order with single dispatcher thread
+        Appears as if strided
+        Not queued, read-ahead buffer required
+
+    Memory usage: (maximum transfer length) * (number of threads)

docs/changes.txt

@@ -34,3 +34,11 @@ v0.9
 * Make I/O scheduling deterministic for better sequential performance on HDDs.
 * Merge unmap ranges across requests for better space efficiency.
 * Flush file metadata after one minute of inactivity.
+
+v1.0
+
+* Change maximum transfer length to 1MB to maximize sequential performance.
+* Revert deterministic I/O scheduling to handle concurrent I/O's as intended.
+* Improve handling buffers for small-sized I/O's.
+* Fix bugs in unaligned (page-based) I/O's.
+* Fix inactivity timer.

docs/design.txt

@@ -39,13 +39,8 @@ Asynchronous I/O:
 
 --------------------------------------------------------------------------------
 
-Scheduling requests in dispatcher:
-    worker = (address / 1048576) % (# of workers)
-    choose next worker if QD >= 32, wait if all full
-
-    characteristic:
-        requests parallelized if depth > 32
-        requests serialized if size < 1048576 bytes
+One worker thread per dispatcher thread:
+    Bypass/Synchronous/Asynchronous I/O
 
 ChunkDiskService:
     Chunks:

main.cpp

@@ -302,7 +302,7 @@ DWORD CreateStorageUnit(PWSTR chunkdisk_file, BOOLEAN write_protected, PWSTR pip
     err = [&params, write_protected, pipe_name, &unit]() -> DWORD
     {
         constexpr wchar_t ProductId[] = L"ChunkDisk";
-        constexpr wchar_t ProductRevision[] = L"0.9";
+        constexpr wchar_t ProductRevision[] = L"1.0";
         auto unit_params = SPD_STORAGE_UNIT_PARAMS();
 
         UuidCreate(&unit_params.Guid);