fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * CDDL HEADER START
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * The contents of this file are subject to the terms of the
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * Common Development and Distribution License (the "License").
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * You may not use this file except in compliance with the License.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * See the License for the specific language governing permissions
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * and limitations under the License.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * When distributing Covered Code, include this CDDL HEADER in each
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
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fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * fields enclosed by brackets "[]" replaced with your own identifying
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fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * Use is subject to license terms.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * Copyright (c) 2013, 2015 by Delphix. All rights reserved.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * This tunable disables predictive prefetch. Note that it leaves "prescient"
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * prefetch (e.g. prefetch for zfs send) intact. Unlike predictive prefetch,
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * prescient prefetch never issues i/os that end up not being needed,
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * so it can't hurt performance.
numstreams++;
if (zfs_prefetch_disable)
if (blkid == 0)
if (fetch_data) {
pf_nblks = 0;
for (int i = 0; i < pf_nblks; i++) {