/*****************************************************************************
- * RRDtool 1.2.23 Copyright by Tobi Oetiker, 1997-2007
+ * RRDtool 1.2.99907080300 Copyright by Tobi Oetiker, 1997-2007
*****************************************************************************
* rrd_open.c Open an RRD File
*****************************************************************************
#define MEMBLK 8192
/* DEBUG 2 prints information obtained via mincore(2) */
-//#define DEBUG 2
+#define DEBUG 1
/* do not calculate exact madvise hints but assume 1 page for headers and
* set DONTNEED for the rest, which is assumed to be data */
-//#define ONE_PAGE 1
/* Avoid calling madvise on areas that were already hinted. May be benefical if
* your syscalls are very slow */
-#define CHECK_MADVISE_OVERLAPS 1
#ifdef HAVE_MMAP
/* the cast to void* is there to avoid this warning seen on ia64 with certain
#define PAGE_START(addr) ((addr)&(~(_page_size-1)))
#endif
-#ifdef HAVE_MMAP
-/* vector of last madvise hint */
-typedef struct _madvise_vec_t {
- void *start;
- ssize_t length;
-} _madvise_vec_t;
-_madvise_vec_t _madv_vec = { NULL, 0 };
-#endif
-
-#if defined CHECK_MADVISE_OVERLAPS
-#define _madvise(_start, _off, _hint) \
- if ((_start) != _madv_vec.start && (ssize_t)(_off) != _madv_vec.length) { \
- _madv_vec.start = (_start) ; _madv_vec.length = (_off); \
- madvise((_start), (_off), (_hint)); \
- }
-#else
-#define _madvise(_start, _off, _hint) \
- madvise((_start), (_off), (_hint))
-#endif
/* Open a database file, return its header and an open filehandle,
* positioned to the first cdp in the first rra.
#if defined MAP_NONBLOCK
mm_flags |= MAP_NONBLOCK; /* just populate ptes */
#endif
-#ifdef USE_DIRECT_IO
- } else {
- flags |= O_DIRECT;
-#endif
}
-#ifdef O_NONBLOCK
- flags |= O_NONBLOCK;
-#endif
if ((rrd_file->fd = open(file_name, flags, mode)) < 0) {
rrd_set_error("opening '%s': %s", file_name, rrd_strerror(errno));
When we stop reading, it is highly unlikely that we start up again.
In this manner we actually save time and diskaccess (and buffer cache).
Thanks to Dave Plonka for the Idea of using POSIX_FADV_RANDOM here. */
- if (0 != posix_fadvise(rrd_file->fd, 0, 0, POSIX_FADV_RANDOM)) {
- rrd_set_error("setting POSIX_FADV_RANDOM on '%s': %s", file_name,
- rrd_strerror(errno));
- goto out_close;
- }
+ posix_fadvise(rrd_file->fd, 0, 0, POSIX_FADV_RANDOM);
#endif
/*
#ifdef USE_MADVISE
if (rdwr & RRD_COPY) {
/* We will read everything in a moment (copying) */
- _madvise(data, rrd_file->file_len, MADV_WILLNEED | MADV_SEQUENTIAL);
+ madvise(data, rrd_file->file_len, MADV_WILLNEED | MADV_SEQUENTIAL);
} else {
-# ifndef ONE_PAGE
/* We do not need to read anything in for the moment */
- _madvise(data, rrd_file->file_len, MADV_RANDOM);
+ madvise(data, rrd_file->file_len, MADV_RANDOM);
/* the stat_head will be needed soonish, so hint accordingly */
- _madvise(data, sizeof(stat_head_t), MADV_WILLNEED | MADV_RANDOM);
-
-# else
-/* alternatively: keep 1 page worth of data, likely headers,
- * don't need the rest. */
- _madvise(data, _page_size, MADV_WILLNEED | MADV_SEQUENTIAL);
- _madvise(data + _page_size, (rrd_file->file_len >= _page_size)
- ? rrd_file->file_len - _page_size : 0, MADV_DONTNEED);
-# endif
+ madvise(data, sizeof(stat_head_t), MADV_WILLNEED | MADV_RANDOM);
}
#endif
rrd->stat_head->version);
goto out_nullify_head;
}
-#if defined USE_MADVISE && !defined ONE_PAGE
+#if defined USE_MADVISE
/* the ds_def will be needed soonish, so hint accordingly */
- _madvise(data + PAGE_START(offset),
- sizeof(ds_def_t) * rrd->stat_head->ds_cnt,
- MADV_WILLNEED);
+ madvise(data + PAGE_START(offset),
+ sizeof(ds_def_t) * rrd->stat_head->ds_cnt, MADV_WILLNEED);
#endif
__rrd_read(rrd->ds_def, ds_def_t,
rrd->stat_head->ds_cnt);
-#if defined USE_MADVISE && !defined ONE_PAGE
+#if defined USE_MADVISE
/* the rra_def will be needed soonish, so hint accordingly */
- _madvise(data + PAGE_START(offset),
- sizeof(rra_def_t) * rrd->stat_head->rra_cnt,
- MADV_WILLNEED);
+ madvise(data + PAGE_START(offset),
+ sizeof(rra_def_t) * rrd->stat_head->rra_cnt, MADV_WILLNEED);
#endif
__rrd_read(rrd->rra_def, rra_def_t,
rrd->stat_head->rra_cnt);
#endif
rrd->live_head->last_up_usec = 0;
} else {
-#if defined USE_MADVISE && !defined ONE_PAGE
+#if defined USE_MADVISE
/* the live_head will be needed soonish, so hint accordingly */
- _madvise(data + PAGE_START(offset),
- sizeof(live_head_t), MADV_WILLNEED);
+ madvise(data + PAGE_START(offset),
+ sizeof(live_head_t), MADV_WILLNEED);
#endif
__rrd_read(rrd->live_head, live_head_t,
1);
}
-/* Close a reference to an rrd_file. */
+#if defined DEBUG && DEBUG > 1
+/* Print list of in-core pages of a the current rrd_file. */
static
-void mincore_print(rrd_file_t *rrd_file,char * mark){
+void mincore_print(
+ rrd_file_t *rrd_file,
+ char *mark)
+{
#ifdef HAVE_MMAP
/* pretty print blocks in core */
off_t off;
if (off == 0)
was_in = is_in;
if (was_in != is_in) {
- fprintf(stderr, "%s: %sin core: %p len %ld\n",mark,
+ 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, "mincore: %s", rrd_strerror(errno));
}
#else
- fprintf(stderr, "sorry mincore only works with mmap");
+ fprintf(stderr, "sorry mincore only works with mmap");
#endif
}
+#endif /* defined DEBUG && DEBUG > 1 */
/* drop cache except for the header and the active pages */
-void
-rrd_dontneed (
+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;
+ 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");
+ 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;
+ 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){
+ 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);
+ 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);
+ 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);
+ }
+ dontneed_start = active_block;
+ /* do not release 'hot' block if update for this RAA will occur
+ * within 10 minutes */
+ if (rrd->stat_head->pdp_step * rrd->rra_def[i].pdp_cnt -
+ rrd->live_head->last_up % (rrd->stat_head->pdp_step *
+ rrd->rra_def[i].pdp_cnt) < 10 * 60) {
+ dontneed_start += _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);
+ 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);
+ 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");
+ mincore_print(rrd_file, "after");
#endif
}
rrd_file_t *rrd_file)
{
int ret;
+
#ifdef HAVE_MMAP
+ ret = msync(rrd_file->file_start, rrd_file->file_len, MS_ASYNC);
+ if (ret != 0)
+ rrd_set_error("msync rrd_file: %s", rrd_strerror(errno));
ret = munmap(rrd_file->file_start, rrd_file->file_len);
if (ret != 0)
rrd_set_error("munmap rrd_file: %s", rrd_strerror(errno));
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
+ /* mimic fseek, which returns 0 upon success */
+ return ret < 0; //XXX: or just ret to mimic lseek
}
}
-/* read count bytes into buffer buf, starting at rrd_file->pos.
+/* Read count bytes into buffer buf, starting at rrd_file->pos.
* Returns the number of bytes read or <0 on error. */
inline ssize_t rrd_read(
{
#ifdef HAVE_MMAP
size_t _cnt = count;
- ssize_t _surplus = rrd_file->pos + _cnt - rrd_file->file_len;
+ ssize_t _surplus;
+ if (rrd_file->pos > rrd_file->file_len || _cnt == 0) /* EOF */
+ return 0;
+ if (buf == NULL)
+ return -1; /* EINVAL */
+ _surplus = rrd_file->pos + _cnt - rrd_file->file_len;
if (_surplus > 0) { /* short read */
_cnt -= _surplus;
}
}
-/* write count bytes from buffer buf to the current position
+/* Write count bytes from buffer buf to the current position
* rrd_file->pos of rrd_file->fd.
- * Returns the number of bytes written. */
+ * Returns the number of bytes written or <0 on error. */
inline ssize_t rrd_write(
rrd_file_t *rrd_file,
size_t count)
{
#ifdef HAVE_MMAP
+ if (count == 0)
+ return 0;
+ if (buf == NULL)
+ return -1; /* EINVAL */
memcpy(rrd_file->file_start + rrd_file->pos, buf, count);
rrd_file->pos += count;
return count; /* mimmic write() semantics */
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