From e7a96b6403f88b7e4bbac18350b560d8e91f565d Mon Sep 17 00:00:00 2001 From: Andriy Gapon Date: Fri, 14 Apr 2017 18:20:56 +0000 Subject: [PATCH] 7541 zpool import/tryimport ioctl returns ENOMEM because provided buffer is too small for config illumos/illumos-gate@8b65a70b763232c90a91f31eb2010314c02ed338 https://github.com/illumos/illumos-gate/commit/8b65a70b763232c90a91f31eb2010314c02ed338 https://www.illumos.org/issues/7541 When calling zpool import, zpool does a few ioctls to ZFS. zpool allocates a buffer in userland and passes it to the kernel so that ZFS can copy info into it. ZFS will use it to put the nvlist that describes the pool configuration. If the allocated buffer is too small, ZFS will return ENOMEM and the call will have to be redone. This wastes CPU time and slows down the import process. This happens very often for the ZFS_IOC_POOL_TRYIMPORT call. Reviewed by: Matthew Ahrens Reviewed by: Dan Kimmel Approved by: Dan McDonald Author: Pavel Zakharov --- lib/libzfs/common/libzfs_impl.h | 2 ++ lib/libzfs/common/libzfs_import.c | 9 +++++---- 2 files changed, 7 insertions(+), 4 deletions(-) diff --git a/lib/libzfs/common/libzfs_impl.h b/lib/libzfs/common/libzfs_impl.h index 6450ce609fd7..d21f167bf38d 100644 --- a/lib/libzfs/common/libzfs_impl.h +++ b/lib/libzfs/common/libzfs_impl.h @@ -130,6 +130,8 @@ typedef enum { SHARED_SMB = 0x4 } zfs_share_type_t; +#define CONFIG_BUF_MINSIZE 65536 + int zfs_error(libzfs_handle_t *, int, const char *); int zfs_error_fmt(libzfs_handle_t *, int, const char *, ...); void zfs_error_aux(libzfs_handle_t *, const char *, ...); diff --git a/lib/libzfs/common/libzfs_import.c b/lib/libzfs/common/libzfs_import.c index 3b6a6d468eea..fe2f82b5bd85 100644 --- a/lib/libzfs/common/libzfs_import.c +++ b/lib/libzfs/common/libzfs_import.c @@ -21,7 +21,7 @@ /* * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. - * Copyright (c) 2012, 2015 by Delphix. All rights reserved. + * Copyright (c) 2012, 2016 by Delphix. All rights reserved. * Copyright 2015 RackTop Systems. * Copyright 2016 Nexenta Systems, Inc. */ @@ -380,13 +380,14 @@ refresh_config(libzfs_handle_t *hdl, nvlist_t *config) { nvlist_t *nvl; zfs_cmd_t zc = { 0 }; - int err; + int err, dstbuf_size; if (zcmd_write_conf_nvlist(hdl, &zc, config) != 0) return (NULL); - if (zcmd_alloc_dst_nvlist(hdl, &zc, - zc.zc_nvlist_conf_size * 2) != 0) { + dstbuf_size = MAX(CONFIG_BUF_MINSIZE, zc.zc_nvlist_conf_size * 4); + + if (zcmd_alloc_dst_nvlist(hdl, &zc, dstbuf_size) != 0) { zcmd_free_nvlists(&zc); return (NULL); }