More work on the synthetic read benchmark

[bluesky.git] / bluesky / cache.c

diff --git a/bluesky/cache.c b/bluesky/cache.c
index d8ef5fa..16e3d81 100644 (file)
--- a/bluesky/cache.c
+++ b/bluesky/cache.c
@@ -235,8 +235,11 @@ static void drop_caches(BlueSkyInode *inode)
  * memory-mapped from log file or similar, so the kernel can drop this clean
  * data from memory for us and hence memory management isn't too important.
  * Mainly, we'll want to drop references to data that hasn't been accessed in a
- * while so that it is possible to reclaim log segments on disk. */
-static void flushd_clean(BlueSkyFS *fs)
+ * while so that it is possible to reclaim log segments on disk.
+ *
+ * If aggressive is set, try much harder to drop data from the caches to free
+ * up space. */
+static void flushd_clean(BlueSkyFS *fs, int aggressive)
 {
     g_mutex_lock(fs->lock);
 
@@ -251,7 +254,7 @@ static void flushd_clean(BlueSkyFS *fs)
         inode = fs->accessed_list.prev->data;
 
         uint64_t elapsed = bluesky_get_current_time() - inode->access_time;
-        if (elapsed < CACHE_DROP_DELAY)
+        if (elapsed < CACHE_DROP_DELAY && !aggressive)
             break;
 
         if (bluesky_verbose) {
@@ -325,12 +328,14 @@ void bluesky_cachefile_gc(BlueSkyFS *fs)
          * then we'll just skip the file on this pass. */
         if (g_mutex_trylock(cachefile->lock)) {
             int64_t age = bluesky_get_current_time() - cachefile->atime;
-            g_print("%s addr=%p mapcount=%d refcount=%d atime_age=%f",
-                    cachefile->filename, cachefile->addr, cachefile->mapcount,
-                    cachefile->refcount, age / 1e6);
-            if (cachefile->fetching)
-                g_print(" (fetching)");
-            g_print("\n");
+            if (bluesky_verbose) {
+                g_print("%s addr=%p mapcount=%d refcount=%d size=%d atime_age=%f",
+                        cachefile->filename, cachefile->addr, cachefile->mapcount,
+                        cachefile->refcount, cachefile->disk_used, age / 1e6);
+                if (cachefile->fetching)
+                    g_print(" (fetching)");
+                g_print("\n");
+            }
 
             gboolean deletion_candidate = FALSE;
             if (g_atomic_int_get(&fs->log->disk_used)
@@ -350,14 +355,19 @@ void bluesky_cachefile_gc(BlueSkyFS *fs)
             }
 
             if (deletion_candidate) {
-                g_print("   ...deleting\n");
+                if (bluesky_verbose) {
+                    g_print("   ...deleting\n");
+                }
                 if (unlinkat(fs->log->dirfd, cachefile->filename, 0) < 0) {
                     fprintf(stderr, "Unable to unlink journal %s: %m\n",
                             cachefile->filename);
                 }
 
-                g_atomic_int_add(&fs->log->disk_used, -(cachefile->len / 1024));
+                g_atomic_int_add(&fs->log->disk_used, -cachefile->disk_used);
                 g_hash_table_remove(fs->log->mmap_cache, cachefile->filename);
+                bluesky_rangeset_free(cachefile->items);
+                if (cachefile->prefetches != NULL)
+                    bluesky_rangeset_free(cachefile->prefetches);
                 g_mutex_unlock(cachefile->lock);
                 g_mutex_free(cachefile->lock);
                 g_cond_free(cachefile->cond);
@@ -370,6 +380,7 @@ void bluesky_cachefile_gc(BlueSkyFS *fs)
         files = g_list_delete_link(files, files);
     }
     g_list_free(files);
+    g_print("\nEnding cache size: %d kB\n", fs->log->disk_used);
 
     g_mutex_unlock(fs->log->mmap_lock);
 }
@@ -389,8 +400,17 @@ static gpointer flushd_task(BlueSkyFS *fs)
 
     flushd_dirty(fs);
     flushd_cloud(fs);
-    flushd_clean(fs);
+    flushd_clean(fs, 0);
     bluesky_cachefile_gc(fs);
+
+    /* If running out of disk cache space, make another more aggressive pass to
+     * free up space. */
+    if (g_atomic_int_get(&fs->log->disk_used) > bluesky_options.cache_size) {
+        g_print("Still short on disk space, trying again to free space...\n");
+        flushd_clean(fs, 1);
+        bluesky_cachefile_gc(fs);
+    }
+
     g_mutex_unlock(fs->flushd_lock);
 
     return NULL;