/* n_data was the first entry we added after the initial file format design */
#define HEADER_SIZE_MIN ALIGN64(offsetof(Header, n_data))
+/* How many entries to keep in the entry array chain cache at max */
+#define CHAIN_CACHE_MAX 20
+
void journal_file_close(JournalFile *f) {
assert(f);
if (f->mmap)
mmap_cache_unref(f->mmap);
+ hashmap_free_free(f->chain_cache);
+
#ifdef HAVE_XZ
free(f->compress_buffer);
#endif
return r;
}
+typedef struct ChainCacheItem {
+ uint64_t first; /* the array at the begin of the chain */
+ uint64_t array; /* the cached array */
+ uint64_t begin; /* the first item in the cached array */
+ uint64_t total; /* the total number of items in all arrays before this one in the chain */
+} ChainCacheItem;
+
+static void chain_cache_put(
+ Hashmap *h,
+ ChainCacheItem *ci,
+ uint64_t first,
+ uint64_t array,
+ uint64_t begin,
+ uint64_t total) {
+
+ if (!ci) {
+ /* If the chain item to cache for this chain is the
+ * first one it's not worth caching anything */
+ if (array == first)
+ return;
+
+ if (hashmap_size(h) >= CHAIN_CACHE_MAX)
+ ci = hashmap_steal_first(h);
+ else {
+ ci = new(ChainCacheItem, 1);
+ if (!ci)
+ return;
+ }
+
+ ci->first = first;
+
+ if (hashmap_put(h, &ci->first, ci) < 0) {
+ free(ci);
+ return;
+ }
+ } else
+ assert(ci->first == first);
+
+ ci->array = array;
+ ci->begin = begin;
+ ci->total = total;
+}
+
static int generic_array_get(JournalFile *f,
uint64_t first,
uint64_t i,
Object **ret, uint64_t *offset) {
Object *o;
- uint64_t p = 0, a;
+ uint64_t p = 0, a, t = 0;
int r;
+ ChainCacheItem *ci;
assert(f);
a = first;
+
+ /* Try the chain cache first */
+ ci = hashmap_get(f->chain_cache, &first);
+ if (ci && i > ci->total) {
+ a = ci->array;
+ i -= ci->total;
+ t = ci->total;
+ }
+
while (a > 0) {
- uint64_t n;
+ uint64_t k;
r = journal_file_move_to_object(f, OBJECT_ENTRY_ARRAY, a, &o);
if (r < 0)
return r;
- n = journal_file_entry_array_n_items(o);
- if (i < n) {
+ k = journal_file_entry_array_n_items(o);
+ if (i < k) {
p = le64toh(o->entry_array.items[i]);
- break;
+ goto found;
}
- i -= n;
+ i -= k;
+ t += k;
a = le64toh(o->entry_array.next_entry_array_offset);
}
- if (a <= 0 || p <= 0)
- return 0;
+ return 0;
+
+found:
+ /* Let's cache this item for the next invocation */
+ chain_cache_put(f->chain_cache, ci, first, a, o->entry_array.items[0], t);
r = journal_file_move_to_object(f, OBJECT_ENTRY, p, &o);
if (r < 0)
bool subtract_one = false;
Object *o, *array = NULL;
int r;
+ ChainCacheItem *ci;
assert(f);
assert(test_object);
+ /* Start with the first array in the chain */
a = first;
+
+ ci = hashmap_get(f->chain_cache, &first);
+ if (ci && n > ci->total) {
+ /* Ah, we have iterated this bisection array chain
+ * previously! Let's see if we can skip ahead in the
+ * chain, as far as the last time. But we can't jump
+ * backwards in the chain, so let's check that
+ * first. */
+
+ r = test_object(f, ci->begin, needle);
+ if (r < 0)
+ return r;
+
+ if (r == TEST_LEFT) {
+ /* OK, what we are looking for is right of th
+ * begin of this EntryArray, so let's jump
+ * straight to previously cached array in the
+ * chain */
+
+ a = ci->array;
+ n -= ci->total;
+ t = ci->total;
+ }
+ }
+
while (a > 0) {
uint64_t left, right, k, lp;
if (subtract_one && t == 0 && i == 0)
return 0;
+ /* Let's cache this item for the next invocation */
+ chain_cache_put(f->chain_cache, ci, first, a, array->entry_array.items[0], t);
+
if (subtract_one && i == 0)
p = last_p;
else if (subtract_one)
goto fail;
}
+ f->chain_cache = hashmap_new(uint64_hash_func, uint64_compare_func);
+ if (!f->chain_cache) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
f->fd = open(f->path, f->flags|O_CLOEXEC, f->mode);
if (f->fd < 0) {
r = -errno;
return true;
}
+ /* Are the data objects properly indexed by field objects? */
+ if (JOURNAL_HEADER_CONTAINS(f->header, n_data) &&
+ JOURNAL_HEADER_CONTAINS(f->header, n_fields) &&
+ le64toh(f->header->n_data) > 0 &&
+ le64toh(f->header->n_fields) == 0)
+ return true;
+
if (max_file_usec > 0) {
usec_t t, h;