From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:30518 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966379AbdI0CbO (ORCPT ); Tue, 26 Sep 2017 22:31:14 -0400 Date: Tue, 26 Sep 2017 19:31:10 -0700 From: "Darrick J. Wong" Subject: Re: [PATCH] db: increase metadump's default overly long extent discard threshold Message-ID: <20170927023110.GN5020@magnolia> References: <20170927010234.GJ5020@magnolia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Eric Sandeen Cc: xfs On Tue, Sep 26, 2017 at 09:21:37PM -0500, Eric Sandeen wrote: > On 9/26/17 8:02 PM, Darrick J. Wong wrote: > > Back in 88b8e1d6d7 ("Make xfs_metadump more robust against bad data"), > > metadump grew the ability to ignore a directory extent if it was longer > > than 20 blocks. Presumably this was to protect metadump from dumping > > absurdly long extents resulting from bmbt corruption, but it's certainly > > possible to create a directory with an extent longer than 20 blocks. > > Hilariously, the discards happen with no warning unless the caller > > explicitly set -w. > > > > This was raised to 1000 blocks in 7431d134fe8 ("Increase default maximum > > extent size for xfs_metadump when copying..."), but it's still possible > > to create a directory with an extent longer than 1000 blocks. > > > > Increase the threshold to MAXEXTLEN blocks because it's totally valid > > for the filesystem to create extents up to that length. > > > > Signed-off-by: Darrick J. Wong > > This is documented in the manpage as being 1000, so that needs an update > as well. Ok. > And should the warning be made unconditional, if that's what burned > you? Nah, since most of the other warnings in metadump are about things that look like bad metadata. --D > > -Eric > > > --- > > db/metadump.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/db/metadump.c b/db/metadump.c > > index c179480..c8eb8f0 100644 > > --- a/db/metadump.c > > +++ b/db/metadump.c > > @@ -32,7 +32,7 @@ > > #include "field.h" > > #include "dir2.h" > > > > -#define DEFAULT_MAX_EXT_SIZE 1000 > > +#define DEFAULT_MAX_EXT_SIZE MAXEXTLEN > > > > /* > > * It's possible that multiple files in a directory (or attributes > > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html