+ if (version < 3) {
+ rrd->live_head = (live_head_t *) malloc(sizeof(live_head_t));
+ if (rrd->live_head == NULL) {
+ rrd_set_error("live_head_t malloc");
+ goto out_close;
+ }
+#ifdef HAVE_MMAP
+ memmove(&rrd->live_head->last_up, data + offset, sizeof(long));
+ offset += sizeof(long);
+#else
+ offset += read(rrd_file->fd, &rrd->live_head->last_up, sizeof(long));
+#endif
+ rrd->live_head->last_up_usec = 0;
+ } else {
+#if defined USE_MADVISE && !defined ONE_PAGE
+ /* the live_head will be needed soonish, so hint accordingly */
+ _madvise(data + PAGE_START(offset),
+ sizeof(live_head_t), MADV_WILLNEED);
+#endif
+ __rrd_read(rrd->live_head, live_head_t,
+ 1);
+ }
+//XXX: This doesn't look like it needs madvise
+ __rrd_read(rrd->pdp_prep, pdp_prep_t,
+ rrd->stat_head->ds_cnt);
+
+//XXX: This could benefit from madvise()ing
+ __rrd_read(rrd->cdp_prep, cdp_prep_t,
+ rrd->stat_head->rra_cnt * rrd->stat_head->ds_cnt);
+
+//XXX: This could benefit from madvise()ing
+ __rrd_read(rrd->rra_ptr, rra_ptr_t,
+ rrd->stat_head->rra_cnt);
+
+ rrd_file->header_len = offset;
+ rrd_file->pos = offset;
+ out_done:
+ return (rrd_file);
+ out_nullify_head:
+ rrd->stat_head = NULL;
+ out_close:
+ close(rrd_file->fd);
+ out_free:
+ free(rrd_file);
+ return NULL;
+}
+
+
+/* Close a reference to an rrd_file. */
+static
+void mincore_print(rrd_file_t *rrd_file,char * mark){
+#ifdef HAVE_MMAP
+ /* pretty print blocks in core */
+ off_t off;
+ unsigned char *vec;
+ ssize_t _page_size = sysconf(_SC_PAGESIZE);
+
+ off = rrd_file->file_len +
+ ((rrd_file->file_len + _page_size - 1) / _page_size);
+ vec = malloc(off);
+ if (vec != NULL) {
+ memset(vec, 0, off);
+ if (mincore(rrd_file->file_start, rrd_file->file_len, vec) == 0) {
+ int prev;
+ unsigned is_in = 0, was_in = 0;
+
+ for (off = 0, prev = 0; off < rrd_file->file_len; ++off) {
+ is_in = vec[off] & 1; /* if lsb set then is core resident */
+ if (off == 0)
+ was_in = is_in;
+ if (was_in != is_in) {
+ fprintf(stderr, "%s: %sin core: %p len %ld\n",mark,
+ was_in ? "" : "not ", vec + prev, off - prev);
+ was_in = is_in;
+ prev = off;
+ }
+ }
+ fprintf(stderr,
+ "%s: %sin core: %p len %ld\n", mark,
+ was_in ? "" : "not ", vec + prev, off - prev);
+ } else
+ fprintf(stderr, "mincore: %s", rrd_strerror(errno));
+ }
+#else
+ fprintf(stderr, "sorry mincore only works with mmap");
+#endif
+}
+
+
+/* drop cache except for the header and the active pages */
+void
+rrd_dontneed (
+ rrd_file_t *rrd_file,
+ rrd_t *rrd){
+ unsigned long dontneed_start;
+ unsigned long rra_start;
+ unsigned long active_block;
+ unsigned long i;
+ ssize_t _page_size = sysconf(_SC_PAGESIZE);
+
+#if defined DEBUG && DEBUG > 1
+ mincore_print(rrd_file,"before");
+#endif
+
+ /* ignoring errors from RRDs that are smaller then the file_len+rounding */
+ rra_start = rrd_file->header_len;
+ dontneed_start = PAGE_START(rra_start)+_page_size;
+ for (i = 0; i < rrd->stat_head->rra_cnt; ++i) {
+ active_block =
+ PAGE_START(rra_start
+ + rrd->rra_ptr[i].cur_row
+ * rrd->stat_head->ds_cnt
+ * sizeof(rrd_value_t));
+ if (active_block > dontneed_start){
+#ifdef USE_MADVISE
+ _madvise(rrd_file->file_start + dontneed_start,
+ active_block-dontneed_start-1,
+ MADV_DONTNEED);
+#endif
+/* in linux at least only fadvise DONTNEED seems to purge pages from cache */
+#ifdef HAVE_POSIX_FADVISE
+ posix_fadvise(rrd_file->fd, dontneed_start, active_block-dontneed_start-1, POSIX_FADV_DONTNEED);
+#endif
+ }
+ dontneed_start = active_block + _page_size;
+ rra_start += rrd->rra_def[i].row_cnt * rrd->stat_head->ds_cnt * sizeof(rrd_value_t);
+ }
+#ifdef USE_MADVISE
+ _madvise(rrd_file->file_start + dontneed_start,
+ rrd_file->file_len - dontneed_start,
+ MADV_DONTNEED);
+#endif
+#ifdef HAVE_POSIX_FADVISE
+ posix_fadvise(rrd_file->fd, dontneed_start, rrd_file->file_len-dontneed_start, POSIX_FADV_DONTNEED);
+#endif
+#if defined DEBUG && DEBUG > 1
+ mincore_print(rrd_file,"after");
+#endif
+}
+
+int rrd_close(
+ rrd_file_t *rrd_file)
+{
+ int ret;
+#ifdef HAVE_MMAP
+ ret = munmap(rrd_file->file_start, rrd_file->file_len);
+ if (ret != 0)
+ rrd_set_error("munmap rrd_file: %s", rrd_strerror(errno));
+#endif
+ ret = close(rrd_file->fd);
+ if (ret != 0)
+ rrd_set_error("closing file: %s", rrd_strerror(errno));
+ free(rrd_file);
+ rrd_file = NULL;
+ return ret;
+}
+
+
+/* Set position of rrd_file. */
+
+off_t rrd_seek(
+ rrd_file_t *rrd_file,
+ off_t off,
+ int whence)
+{
+ off_t ret = 0;
+
+#ifdef HAVE_MMAP
+ if (whence == SEEK_SET)
+ rrd_file->pos = off;
+ else if (whence == SEEK_CUR)
+ rrd_file->pos += off;
+ else if (whence == SEEK_END)
+ rrd_file->pos = rrd_file->file_len + off;
+#else
+ ret = lseek(rrd_file->fd, off, whence);
+ if (ret < 0)
+ rrd_set_error("lseek: %s", rrd_strerror(errno));
+ rrd_file->pos = ret;
+#endif
+//XXX: mimic fseek, which returns 0 upon success
+ return ret == -1; //XXX: or just ret to mimic lseek