X-Git-Url: http://git.vrable.net/?a=blobdiff_plain;f=store.cc;h=8f2c8b328c2d7cacea3ca4c3683993532d1a7980;hb=def20364a3596d7b1fa4a07f3d3ee056cfff2d1e;hp=26797b319ed635341d1deeedf6bd161110644590;hpb=ac33ae99de4a6aa9cfaca2f7fd6746758264758e;p=cumulus.git

diff --git a/store.cc b/store.cc
index 26797b3..8f2c8b3 100644
--- a/store.cc
+++ b/store.cc
@@ -16,7 +16,9 @@
 #include <fcntl.h>
 #include <time.h>
 
+#include <algorithm>
 #include <list>
+#include <map>
 #include <set>
 #include <string>
 #include <iostream>
@@ -24,11 +26,15 @@
 #include "store.h"
 #include "ref.h"
 
+using std::max;
 using std::list;
+using std::map;
 using std::set;
 using std::string;
 
-static char *const filter_program[] = {"bzip2", "-c", NULL};
+/* Default filter program is bzip2 */
+const char *filter_program = "bzip2 -c";
+const char *filter_extension = ".bz2";
 
 static void cloexec(int fd)
 {
@@ -51,7 +57,7 @@ Tarfile::Tarfile(const string &path, const string &segment)
     filter_fd = spawn_filter(real_fd);
 
     if (tar_fdopen(&t, filter_fd, (char *)path.c_str(), NULL,
-                   O_WRONLY | O_CREAT, 0600, TAR_VERBOSE | TAR_GNU) == -1)
+                   O_WRONLY | O_CREAT, 0666, TAR_VERBOSE | TAR_GNU) == -1)
         throw IOException("Error opening Tarfile");
 }
 
@@ -110,7 +116,7 @@ int Tarfile::spawn_filter(int fd_out)
         close(fd_out);
 
         /* Exec the filter program. */
-        execvp(filter_program[0], filter_program);
+        execlp("/bin/sh", "/bin/sh", "-c", filter_program, NULL);
 
         /* Should not reach here except for error cases. */
         fprintf(stderr, "Could not exec filter: %m\n");
@@ -169,24 +175,29 @@ void Tarfile::internal_write_object(const string &path,
 }
 
 /* Estimate the size based on the size of the actual output file on disk.
- * However, the filter may not have written all data yet, and in the event that
- * it is buffering data to a large extent, also use */
+ * However, it might be the case that the filter program is buffering all its
+ * data, and might potentially not write a single byte until we have closed
+ * our end of the pipe.  If we don't do so until we see data written, we have
+ * a problem.  So, arbitrarily pick an upper bound on the compression ratio
+ * that the filter will achieve (128:1), and return a size estimate which is
+ * the larger of a) bytes actually seen written to disk, and b) input
+ * bytes/128. */
 size_t Tarfile::size_estimate()
 {
     struct stat statbuf;
 
-    if (fstat(real_fd, &statbuf) == 0) {
-        size_t disk_size = statbuf.st_size;
-
-        if (disk_size >= size / 128)
-            return disk_size;
-    }
+    if (fstat(real_fd, &statbuf) == 0)
+        return max((int64_t)statbuf.st_size, (int64_t)(size / 128));
 
+    /* Couldn't stat the file on disk, so just return the actual number of
+     * bytes, before compression. */
     return size;
 }
 
 static const size_t SEGMENT_SIZE = 4 * 1024 * 1024;
 
+static map<string, int64_t> group_sizes;
+
 ObjectReference TarSegmentStore::write_object(const char *data, size_t len,
                                               const std::string &group)
 {
@@ -199,7 +210,8 @@ ObjectReference TarSegmentStore::write_object(const char *data, size_t len,
 
         segment->name = generate_uuid();
 
-        string filename = path + "/" + segment->name + ".tar.bz2";
+        string filename = path + "/" + segment->name + ".tar";
+        filename += filter_extension;
         segment->file = new Tarfile(filename, segment->name);
 
         segment->count = 0;
@@ -216,6 +228,8 @@ ObjectReference TarSegmentStore::write_object(const char *data, size_t len,
     segment->file->write_object(id, data, len);
     segment->count++;
 
+    group_sizes[group] += len;
+
     ObjectReference ref(segment->name, id_buf);
 
     // If this segment meets or exceeds the size target, close it so that
@@ -232,6 +246,15 @@ void TarSegmentStore::sync()
         close_segment(segments.begin()->first);
 }
 
+void TarSegmentStore::dump_stats()
+{
+    printf("Data written:\n");
+    for (map<string, int64_t>::iterator i = group_sizes.begin();
+         i != group_sizes.end(); ++i) {
+        printf("    %s: %lld\n", i->first.c_str(), i->second);
+    }
+}
+
 void TarSegmentStore::close_segment(const string &group)
 {
     struct segment_info *segment = segments[group];