+#if defined HAVE_MMAP || defined DEBUG
+ ssize_t _page_size = sysconf(_SC_PAGESIZE);
+#endif
+#if defined DEBUG && DEBUG > 1
+ /* pretty print blocks in core */
+ off_t off;
+ unsigned char *vec;
+
+ 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, "%sin core: %p len %ld\n",
+ was_in ? "" : "not ", vec + prev, off - prev);
+ was_in = is_in;
+ prev = off;
+ }
+ }
+ fprintf(stderr,
+ "%sin core: %p len %ld\n",
+ was_in ? "" : "not ", vec + prev, off - prev);
+ } else
+ fprintf(stderr, "mincore: %s", rrd_strerror(errno));
+ }
+#endif /* DEBUG */
+
+#ifdef USE_MADVISE
+# ifdef ONE_PAGE
+ /* Keep headers around, round up to next page boundary. */
+ ret =
+ PAGE_ALIGN(rrd_file->header_len % _page_size + rrd_file->header_len);
+ if (rrd_file->file_len > ret)
+ _madvise(rrd_file->file_start + ret,
+ rrd_file->file_len - ret, MADV_DONTNEED);
+# else
+ /* ignoring errors from RRDs that are smaller then the file_len+rounding */
+ _madvise(rrd_file->file_start + PAGE_ALIGN_DOWN(rrd_file->header_len),
+ rrd_file->file_len - PAGE_ALIGN(rrd_file->header_len),
+ MADV_DONTNEED);
+# endif
+#endif