bulk move of code to src/ SERVER-4551

1 files changed, 150 insertions, 0 deletions

diff --git a/src/mongo/db/flushtest.cpp b/src/mongo/db/flushtest.cpp
new file mode 100644
index 00000000000..2009d922950
--- /dev/null
+++ b/src/mongo/db/flushtest.cpp
@@ -0,0 +1,150 @@
+/*
+ *    Copyright (C) 2010 10gen Inc.
+ *
+ *    This program is free software: you can redistribute it and/or  modify
+ *    it under the terms of the GNU Affero General Public License, version 3,
+ *    as published by the Free Software Foundation.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU Affero General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Affero General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "pch.h"
+#include <stdio.h>
+#include "../util/goodies.h"
+#include <fcntl.h>
+
+namespace mongo {
+
+#if defined(F_FULLFSYNC)
+    void fullsync(int f) {
+        fcntl( f, F_FULLFSYNC );
+    }
+#else
+    void fullsync(int f) {
+        fdatasync(f);
+    }
+#endif
+
+    int main(int argc, char* argv[], char *envp[] ) {
+        cout << "hello" << endl;
+
+        FILE *f = fopen("/data/db/temptest", "a");
+
+        if ( f == 0 ) {
+            cout << "can't open file\n";
+            return 1;
+        }
+
+        {
+            Timer t;
+            for ( int i = 0; i < 50000; i++ )
+                fwrite("abc", 3, 1, f);
+            cout << "small writes: " << t.millis() << "ms" << endl;
+        }
+
+        {
+            Timer t;
+            for ( int i = 0; i < 10000; i++ ) {
+                fwrite("abc", 3, 1, f);
+                fflush(f);
+                fsync( fileno( f ) );
+            }
+            int ms = t.millis();
+            cout << "flush: " << ms << "ms, " << ms / 10000.0 << "ms/request" << endl;
+        }
+
+        {
+            Timer t;
+            for ( int i = 0; i < 500; i++ ) {
+                fwrite("abc", 3, 1, f);
+                fflush(f);
+                fsync( fileno( f ) );
+                sleepmillis(2);
+            }
+            int ms = t.millis() - 500 * 2;
+            cout << "flush with sleeps: " << ms << "ms, " << ms / 500.0 << "ms/request" << endl;
+        }
+
+        char buf[8192];
+        for ( int pass = 0; pass < 2; pass++ ) {
+            cout << "pass " << pass << endl;
+            {
+                Timer t;
+                int n = 500;
+                for ( int i = 0; i < n; i++ ) {
+                    if ( pass == 0 )
+                        fwrite("abc", 3, 1, f);
+                    else
+                        fwrite(buf, 8192, 1, f);
+                    buf[0]++;
+                    fflush(f);
+                    fullsync(fileno(f));
+                }
+                int ms = t.millis();
+                cout << "fullsync: " << ms << "ms, " << ms / ((double) n) << "ms/request" << endl;
+            }
+
+            {
+                Timer t;
+                for ( int i = 0; i < 500; i++ ) {
+                    if ( pass == 0 )
+                        fwrite("abc", 3, 1, f);
+                    else
+                        fwrite(buf, 8192, 1, f);
+                    buf[0]++;
+                    fflush(f);
+                    fullsync(fileno(f));
+                    sleepmillis(2);
+                }
+                int ms = t.millis() - 2 * 500;
+                cout << "fullsync with sleeps: " << ms << "ms, " << ms / 500.0 << "ms/request" << endl;
+            }
+        }
+
+        // without growing
+        {
+            fclose(f);
+            /* try from beginning of the file, where we aren't appending and changing the file length,
+               to see if this is faster as the directory entry then doesn't have to be flushed (if noatime in effect).
+            */
+            f = fopen("/data/db/temptest", "r+");
+            Timer t;
+            int n = 500;
+            for ( int i = 0; i < n; i++ ) {
+                fwrite("xyz", 3, 1, f);
+                fflush(f);
+                fullsync(fileno(f));
+            }
+            int ms = t.millis();
+            cout << "fullsync without growing: " << ms << "ms, " << ms / ((double) n) << "ms/request" << endl;
+        }
+
+        // without growing, with delay
+        {
+            fclose(f);
+            /* try from beginning of the file, where we aren't appending and changing the file length,
+               to see if this is faster as the directory entry then doesn't have to be flushed (if noatime in effect).
+            */
+            f = fopen("/data/db/temptest", "r+");
+            Timer t;
+            int n = 500;
+            for ( int i = 0; i < n; i++ ) {
+                fwrite("xyz", 3, 1, f);
+                fflush(f);
+                fullsync(fileno(f));
+                sleepmillis(2);
+            }
+            int ms = t.millis() - 2 * 500;
+            cout << "fullsync without growing with sleeps: " << ms << "ms, " << ms / ((double) n) << "ms/request" << endl;
+        }
+
+        return 0;
+    }
+
+} // namespace mongo