コード例 #1
0
ファイル: rec_evict.c プロジェクト: tierney/wiredtiger
/*
 * __wt_rec_evict --
 *	Reconciliation plus eviction.
 */
int
__wt_rec_evict(WT_SESSION_IMPL *session, WT_PAGE *page, int exclusive)
{
	WT_DECL_RET;
	WT_PAGE_MODIFY *mod;
	int merge;

	WT_VERBOSE_RET(session, evict,
	    "page %p (%s)", page, __wt_page_type_string(page->type));

	WT_ASSERT(session, session->excl_next == 0);

	/*
	 * If we get a split-merge page during normal eviction, try to collapse
	 * it.  During close, it will be merged into its parent.
	 */
	mod = page->modify;
	merge = __wt_btree_mergeable(page);
	if (merge && exclusive)
		return (EBUSY);

	WT_ASSERT(session, merge || mod == NULL ||
	    !F_ISSET(mod, WT_PM_REC_SPLIT_MERGE));

	/*
	 * Get exclusive access to the page and review the page and its subtree
	 * for conditions that would block our eviction of the page.  If the
	 * check fails (for example, we find a child page that can't be merged),
	 * we're done.  We have to make this check for clean pages, too: while
	 * unlikely eviction would choose an internal page with children, it's
	 * not disallowed anywhere.
	 *
	 * Note that page->ref may be NULL in some cases (e.g., for root pages
	 * or during salvage).  That's OK if exclusive is set: we won't check
	 * hazard pointers in that case.
	 */
	WT_ERR(__rec_review(session, page->ref, page, exclusive, merge, 1));

	/* Try to merge internal pages. */
	if (merge)
		WT_ERR(__wt_merge_tree(session, page));

	/*
	 * Update the page's modification reference, reconciliation might have
	 * changed it.
	 */
	mod = page->modify;

	/* Count evictions of internal pages during normal operation. */
	if (!exclusive && !merge &&
	    (page->type == WT_PAGE_COL_INT || page->type == WT_PAGE_ROW_INT)) {
		WT_CSTAT_INCR(session, cache_eviction_internal);
		WT_DSTAT_INCR(session, cache_eviction_internal);
	}

	/*
	 * Update the parent and discard the page.
	 */
	if (mod == NULL || !F_ISSET(mod, WT_PM_REC_MASK)) {
		WT_ASSERT(session,
		    exclusive || page->ref->state == WT_REF_LOCKED);

		if (WT_PAGE_IS_ROOT(page))
			__rec_root_update(session);
		else
			__rec_page_clean_update(session, page);

		/* Discard the page. */
		__rec_discard_page(session, page, exclusive);

		WT_CSTAT_INCR(session, cache_eviction_clean);
		WT_DSTAT_INCR(session, cache_eviction_clean);
	} else {
		if (WT_PAGE_IS_ROOT(page))
			__rec_root_update(session);
		else
			WT_ERR(__rec_page_dirty_update(session, page));

		/* Discard the tree rooted in this page. */
		__rec_discard_tree(session, page, exclusive);

		WT_CSTAT_INCR(session, cache_eviction_dirty);
		WT_DSTAT_INCR(session, cache_eviction_dirty);
	}
	if (0) {
err:		/*
		 * If unable to evict this page, release exclusive reference(s)
		 * we've acquired.
		 */
		__rec_excl_clear(session);

		WT_CSTAT_INCR(session, cache_eviction_fail);
		WT_DSTAT_INCR(session, cache_eviction_fail);
	}
	session->excl_next = 0;

	return (ret);
}
コード例 #2
0
ファイル: rec_evict.c プロジェクト: zhliu03/wiredtiger
/*
 * __wt_rec_evict --
 *	Reconciliation plus eviction.
 */
int
__wt_rec_evict(WT_SESSION_IMPL *session, WT_PAGE *page, uint32_t flags)
{
	WT_CONNECTION_IMPL *conn;
	WT_DECL_RET;
	int single;

	conn = S2C(session);

	WT_VERBOSE_RET(session, evict,
	    "page %p (%s)", page, __wt_page_type_string(page->type));

	WT_ASSERT(session, session->excl_next == 0);
	single = LF_ISSET(WT_REC_SINGLE) ? 1 : 0;

	/*
	 * Get exclusive access to the page and review the page and its subtree
	 * for conditions that would block our eviction of the page.  If the
	 * check fails (for example, we find a child page that can't be merged),
	 * we're done.  We have to make this check for clean pages, too: while
	 * unlikely eviction would choose an internal page with children, it's
	 * not disallowed anywhere.
	 *
	 * Note that page->ref may be NULL in some cases (e.g., for root pages
	 * or during salvage).  That's OK if WT_REC_SINGLE is set: we won't
	 * check hazard references in that case.
	 */
	WT_ERR(__rec_review(session, page->ref, page, flags, 1));

	/* Count evictions of internal pages during normal operation. */
	if (!single &&
	    (page->type == WT_PAGE_COL_INT || page->type == WT_PAGE_ROW_INT))
		WT_STAT_INCR(conn->stats, cache_evict_internal);

	/* Update the parent and discard the page. */
	if (page->modify == NULL || !F_ISSET(page->modify, WT_PM_REC_MASK)) {
		WT_STAT_INCR(conn->stats, cache_evict_unmodified);
		WT_ASSERT(session, single || page->ref->state == WT_REF_LOCKED);

		if (WT_PAGE_IS_ROOT(page))
			__rec_root_update(session);
		else
			__rec_page_clean_update(session, page);

		/* Discard the page. */
		__rec_discard_page(session, page, single);
	} else {
		WT_STAT_INCR(conn->stats, cache_evict_modified);

		if (WT_PAGE_IS_ROOT(page))
			__rec_root_update(session);
		else
			WT_ERR(__rec_page_dirty_update(session, page));

		/* Discard the tree rooted in this page. */
		__rec_discard_tree(session, page, single);
	}
	if (0) {
err:		/*
		 * If unable to evict this page, release exclusive reference(s)
		 * we've acquired.
		 */
		__rec_excl_clear(session);
	}
	session->excl_next = 0;

	return (ret);
}