Remove xFileControl() handling from the OPFS VFS altogether, re-routing all syncing through xSync() instead. This eliminates superfluous syncing introduced in [a371374148a2], as discussed in [forum:647d2f811dbc2dfe|forum thread 647d2f811dbc2dfe].

FossilOrigin-Name: f809de7f232c8c2731a877c7bf1ad39fda5b326b2e45e4748cab4dc5e5b535bd

ext/wasm/api/sqlite3-vfs-opfs.c-pp.js

@@ -353,7 +353,6 @@ const installOpfsVfs = function callee(options){
       state.opIds.xClose = i++;
       state.opIds.xDelete = i++;
       state.opIds.xDeleteNoWait = i++;
-      state.opIds.xFileControl = i++;
       state.opIds.xFileSize = i++;
       state.opIds.xLock = i++;
       state.opIds.xOpen = i++;
@@ -718,12 +717,9 @@ const installOpfsVfs = function callee(options){
         return capi.SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN;
       },
       xFileControl: function(pFile, opId, pArg){
-        mTimeStart('xFileControl');
-        const rc = (capi.SQLITE_FCNTL_SYNC===opId)
-              ? opRun('xSync', pFile, 0)
-              : capi.SQLITE_NOTFOUND;
-        mTimeEnd();
-        return rc;
+        /*mTimeStart('xFileControl');
+          mTimeEnd();*/
+        return capi.SQLITE_NOTFOUND;
       },
       xFileSize: function(pFile,pSz64){
         mTimeStart('xFileSize');
@@ -779,8 +775,8 @@ const installOpfsVfs = function callee(options){
         return rc;
       },
       xSync: function(pFile,flags){
-        ++metrics.xSync.count;
         mTimeStart('xSync');
+        ++metrics.xSync.count;
         const rc = opRun('xSync', pFile, flags);
         mTimeEnd();
         return rc;

ext/wasm/speedtest1-worker.html

@@ -23,7 +23,7 @@
     </figure>
     <div class="emscripten" id="module-status">Downloading...</div>
     <div class="emscripten">
-      <progress value="0" max="100" id="module-progress" hidden='1'></progress>  
+      <progress value="0" max="100" id="module-progress" hidden='1'></progress>
     </div><!-- /emscripten bits -->
     <fieldset id='ui-controls' class='hidden'>
       <legend>Options</legend>
@@ -68,10 +68,9 @@
       <ul>
         <li>Control-click the flags to (de)select multiple flags.</li>
         <li>The <tt>--big-transactions</tt> flag is important for two
-          of the bigger tests. Without it, those tests create a
-          combined total of 140k implicit transactions, reducing their
-          speed to an absolute crawl, especially when WASMFS is
-          activated.
+          of the bigger tests. Without it, those tests create many
+          thousands of implicit transactions, reducing the affected
+          tests to an absolute crawl, in particular with OPFS.
         </li>
         <li>The easiest way to try different optimization levels is,
           from this directory:

manifest

@@ -1,5 +1,5 @@
-C Fix\sharmless\scompiler\swarnings.
-D 2023-05-01T18:52:35.233
+C Remove\sxFileControl()\shandling\sfrom\sthe\sOPFS\sVFS\saltogether,\sre-routing\sall\ssyncing\sthrough\sxSync()\sinstead.\sThis\seliminates\ssuperfluous\ssyncing\sintroduced\sin\s[a371374148a2],\sas\sdiscussed\sin\s[forum:647d2f811dbc2dfe|forum\sthread\s647d2f811dbc2dfe].
+D 2023-05-01T19:28:07.032
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -499,7 +499,7 @@ F ext/wasm/api/sqlite3-api-worker1.js 40a5b1813fcbe789f23ae196c833432c8c83e7054d
 F ext/wasm/api/sqlite3-license-version-header.js 0c807a421f0187e778dc1078f10d2994b915123c1223fe752b60afdcd1263f89
 F ext/wasm/api/sqlite3-opfs-async-proxy.js 70914ae97784d3028150bbf252e07a423056c42cc345903c81b5fae661ce512f
 F ext/wasm/api/sqlite3-v-helper.js e5c202a9ecde9ef818536d3f5faf26c03a1a9f5192b1ddea8bdabf30d75ef487
-F ext/wasm/api/sqlite3-vfs-opfs.c-pp.js 98c8baa06f584d344cfb3fa2b044850298c99f38de93308cbfc82d0be3f21c2a
+F ext/wasm/api/sqlite3-vfs-opfs.c-pp.js 89640e4874a60cb2d973306b272384ffb45c7915375c7bb0355c7586f88dc39c
 F ext/wasm/api/sqlite3-wasi.h 25356084cfe0d40458a902afb465df8c21fc4152c1d0a59b563a3fba59a068f9
 F ext/wasm/api/sqlite3-wasm.c 12a096d8e58a0af0589142bae5a3c27a0c7e19846755a1a37d2c206352fbedda
 F ext/wasm/api/sqlite3-worker1-promiser.c-pp.js 2710a06a59620c6bf7ce298ab1fb6c9ce825b9f9379728b74c486db6613beecc
@@ -535,7 +535,7 @@ F ext/wasm/module-symbols.html 841de62fc198988b8330e238c260e70ec93028b096e1a1234
 F ext/wasm/scratchpad-wasmfs-main.html 20cf6f1a8f368e70d01e8c17200e3eaa90f1c8e1029186d836d14b83845fbe06
 F ext/wasm/scratchpad-wasmfs-main.js 4c140457f4d6da9d646a49addd91edb6e9ad1643c6c48e3258b5bce24725dc18
 F ext/wasm/speedtest1-wasmfs.html 7a301f4f5b6ad4f5d37fd6e7ca03a2f5d5547fd289da60a39075a93d7646d354
-F ext/wasm/speedtest1-worker.html fe6b36a63de1012bb9fb4d2fb888b6de9c589c21b0aa3ae054459b0093e077bf
+F ext/wasm/speedtest1-worker.html 82869822e641c1bef3ec0cd2d7d2b6a42d0b4f68a7b160fb2e1dd0b523940a9b
 F ext/wasm/speedtest1-worker.js 13b57c4a41729678a1194014afec2bd5b94435dcfc8d1039dfa9a533ac819ee1
 F ext/wasm/speedtest1.html ff048b4a623aa192e83e143e48f1ce2a899846dd42c023fdedc8772b6e3f07da
 F ext/wasm/split-speedtest1-script.sh a3e271938d4d14ee49105eb05567c6a69ba4c1f1293583ad5af0cd3a3779e205 x
@@ -2068,8 +2068,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P f8c3ed23a6931b1da3b93b3274b132387078112a5c8e8d06b5312c47987d3937
-R 403020ca8f01732564c548c59e1a6a0f
-U drh
-Z 5b27a0031a8a680d5f1735b2f157795b
+P 0a926994691ccb02ea4f0ba3c2e8f728871ae67d24c705fbc0f7af81f38d5f47
+R 1cdaa058190574fdddaef9d6651946a2
+U stephan
+Z 69a7f6e6a615a75d058059bec6f7af85
 # Remove this line to create a well-formed Fossil manifest.

manifest.uuid

@@ -1 +1 @@
-0a926994691ccb02ea4f0ba3c2e8f728871ae67d24c705fbc0f7af81f38d5f47
+f809de7f232c8c2731a877c7bf1ad39fda5b326b2e45e4748cab4dc5e5b535bd