From: Jani Nikula Date: Sun, 1 Sep 2013 15:43:03 +0000 (+0300) Subject: Re: [PATCH 1/3] database: Add notmuch_database_compact_close X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=35e2a5c2df7f2d8d48c5e6051c02f91e627a3863;p=notmuch-archives.git Re: [PATCH 1/3] database: Add notmuch_database_compact_close --- diff --git a/21/2f2ac9b233aff7451c0cb828f5b0f353587662 b/21/2f2ac9b233aff7451c0cb828f5b0f353587662 new file mode 100644 index 000000000..7f412b70a --- /dev/null +++ b/21/2f2ac9b233aff7451c0cb828f5b0f353587662 @@ -0,0 +1,351 @@ +Return-Path: +X-Original-To: notmuch@notmuchmail.org +Delivered-To: notmuch@notmuchmail.org +Received: from localhost (localhost [127.0.0.1]) + by olra.theworths.org (Postfix) with ESMTP id 4A988431FB6 + for ; Sun, 1 Sep 2013 08:43:11 -0700 (PDT) +X-Virus-Scanned: Debian amavisd-new at olra.theworths.org +X-Spam-Flag: NO +X-Spam-Score: -0.7 +X-Spam-Level: +X-Spam-Status: No, score=-0.7 tagged_above=-999 required=5 + tests=[RCVD_IN_DNSWL_LOW=-0.7] autolearn=disabled +Received: from olra.theworths.org ([127.0.0.1]) + by localhost (olra.theworths.org [127.0.0.1]) (amavisd-new, port 10024) + with ESMTP id RNmHTXttIMd2 for ; + Sun, 1 Sep 2013 08:43:05 -0700 (PDT) +Received: from mail-ee0-f42.google.com (mail-ee0-f42.google.com + [74.125.83.42]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (No client + certificate requested) by olra.theworths.org (Postfix) with ESMTPS id + F3175431FAE for ; Sun, 1 Sep 2013 08:43:04 -0700 + (PDT) +Received: by mail-ee0-f42.google.com with SMTP id b45so1889931eek.1 + for ; Sun, 01 Sep 2013 08:43:03 -0700 (PDT) +X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; + d=1e100.net; s=20130820; + h=x-gm-message-state:from:to:subject:in-reply-to:references + :user-agent:date:message-id:mime-version:content-type; + bh=vibekIws0liU6uhc67V/e7GVfvokv/mcXDZb3z4g5TA=; + b=gsHmaDM8xfohEkLA6r8m5wmGnKzI/FirKcEzzHuNgMhYx7kEcYoMOvbnv+TuBSxdOn + hkbBA0p4N8hUb07jAeFT8VO/D0Oo31KzYC/rIcV0DJkNInihNLDVKlJ2WhXs5jOBcHLU + 8wCYx+sz9HvLMOEfFylVALbXmzweR1s5dTua+sTJbuzs4MwWagacTV7qbRIseNDQyLW5 + x/S12AesDGBB/9Vp9a9t2Z1xJkujwWS9hhKl77cxrZ6oYmOe9OAlLuF9RnVOPRGdG/ny + yENW6TSKMkQUlyKha5qtqkNWloglbAslectkhC6odwuHOt9HQXei94t/jE9fELw6YRM0 + dYAQ== +X-Gm-Message-State: + ALoCoQm5bwTgYD2yYOMZ0w/+Wj8WhK5L+3oaksYgcB5XKs52GSEXQfMc23plfVbqrgy2cfX6S77n +X-Received: by 10.14.183.2 with SMTP id p2mr4829714eem.44.1378050183682; + Sun, 01 Sep 2013 08:43:03 -0700 (PDT) +Received: from localhost (dsl-hkibrasgw2-58c36f-91.dhcp.inet.fi. + [88.195.111.91]) + by mx.google.com with ESMTPSA id z12sm14238866eev.6.1969.12.31.16.00.00 + (version=TLSv1.2 cipher=RC4-SHA bits=128/128); + Sun, 01 Sep 2013 08:43:03 -0700 (PDT) +From: Jani Nikula +To: Ben Gamari , notmuch@notmuchmail.org +Subject: Re: [PATCH 1/3] database: Add notmuch_database_compact_close +In-Reply-To: <1377312923-32274-2-git-send-email-bgamari.foss@gmail.com> +References: <1377312923-32274-1-git-send-email-bgamari.foss@gmail.com> + <1377312923-32274-2-git-send-email-bgamari.foss@gmail.com> +User-Agent: Notmuch/0.16 (http://notmuchmail.org) Emacs/24.3.1 + (x86_64-pc-linux-gnu) +Date: Sun, 01 Sep 2013 18:43:03 +0300 +Message-ID: <87ppsssg3c.fsf@nikula.org> +MIME-Version: 1.0 +Content-Type: text/plain +X-BeenThere: notmuch@notmuchmail.org +X-Mailman-Version: 2.1.13 +Precedence: list +List-Id: "Use and development of the notmuch mail system." + +List-Unsubscribe: , + +List-Archive: +List-Post: +List-Help: +List-Subscribe: , + +X-List-Received-Date: Sun, 01 Sep 2013 15:43:11 -0000 + +On Sat, 24 Aug 2013, Ben Gamari wrote: +> This function uses Xapian's Compactor machinery to compact the notmuch +> database. The compacted database is built in a temporary directory and +> later moved into place while the original uncompacted database is +> preserved. +> +> Signed-off-by: Ben Gamari +> --- +> configure | 27 +++++++++++++++-- +> lib/database.cc | 91 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ +> lib/notmuch.h | 15 ++++++++++ +> 3 files changed, 130 insertions(+), 3 deletions(-) +> +> diff --git a/configure b/configure +> index 6166917..ee9e887 100755 +> --- a/configure +> +++ b/configure +> @@ -277,7 +277,8 @@ printf "Checking for Xapian development files... " +> have_xapian=0 +> for xapian_config in ${XAPIAN_CONFIG}; do +> if ${xapian_config} --version > /dev/null 2>&1; then +> - printf "Yes (%s).\n" $(${xapian_config} --version | sed -e 's/.* //') +> + xapian_version=$(${xapian_config} --version | sed -e 's/.* //') +> + printf "Yes (%s).\n" ${xapian_version} +> have_xapian=1 +> xapian_cxxflags=$(${xapian_config} --cxxflags) +> xapian_ldflags=$(${xapian_config} --libs) +> @@ -289,6 +290,21 @@ if [ ${have_xapian} = "0" ]; then +> errors=$((errors + 1)) +> fi +> +> +# Compaction is only supported on Xapian > 1.2.6 +> +have_xapian_compact=0 +> +if [ ${have_xapian} = "1" ]; then +> + printf "Checking for Xapian compact support... " +> + case "${xapian_version}" in +> + 0.*|1.[01].*|1.2.[0-5]) +> + printf "No (only available with Xapian > 1.2.6).\n" ;; +> + [1-9]*.[0-9]*.[0-9]*) +> + have_xapian_compact=1 +> + printf "Yes.\n" ;; +> + *) +> + printf "Unknown version.\n" ;; +> + esac +> +fi +> + +> printf "Checking for GMime development files... " +> have_gmime=0 +> IFS=';' +> @@ -729,6 +745,9 @@ HAVE_STRCASESTR = ${have_strcasestr} +> # build its own version) +> HAVE_STRSEP = ${have_strsep} +> +> +# Whether the Xapian version in use supports compaction +> +HAVE_XAPIAN_COMPACT = ${have_xapian_compact} +> + +> # Whether the getpwuid_r function is standards-compliant +> # (if not, then notmuch will #define _POSIX_PTHREAD_SEMANTICS +> # to enable the standards-compliant version -- needed for Solaris) +> @@ -787,13 +806,15 @@ CONFIGURE_CFLAGS = -DHAVE_GETLINE=\$(HAVE_GETLINE) \$(GMIME_CFLAGS) \\ +> -DHAVE_STRCASESTR=\$(HAVE_STRCASESTR) \\ +> -DHAVE_STRSEP=\$(HAVE_STRSEP) \\ +> -DSTD_GETPWUID=\$(STD_GETPWUID) \\ +> - -DSTD_ASCTIME=\$(STD_ASCTIME) +> + -DSTD_ASCTIME=\$(STD_ASCTIME) \\ +> + -DHAVE_XAPIAN_COMPACT=\$(HAVE_XAPIAN_COMPACT) +> CONFIGURE_CXXFLAGS = -DHAVE_GETLINE=\$(HAVE_GETLINE) \$(GMIME_CFLAGS) \\ +> \$(TALLOC_CFLAGS) -DHAVE_VALGRIND=\$(HAVE_VALGRIND) \\ +> \$(VALGRIND_CFLAGS) \$(XAPIAN_CXXFLAGS) \\ +> -DHAVE_STRCASESTR=\$(HAVE_STRCASESTR) \\ +> -DHAVE_STRSEP=\$(HAVE_STRSEP) \\ +> -DSTD_GETPWUID=\$(STD_GETPWUID) \\ +> - -DSTD_ASCTIME=\$(STD_ASCTIME) +> + -DSTD_ASCTIME=\$(STD_ASCTIME) \\ +> + -DHAVE_XAPIAN_COMPACT=\$(HAVE_XAPIAN_COMPACT) +> CONFIGURE_LDFLAGS = \$(GMIME_LDFLAGS) \$(TALLOC_LDFLAGS) \$(XAPIAN_LDFLAGS) +> EOF +> diff --git a/lib/database.cc b/lib/database.cc +> index 5cc0765..b71751d 100644 +> --- a/lib/database.cc +> +++ b/lib/database.cc +> @@ -268,6 +268,8 @@ notmuch_status_to_string (notmuch_status_t status) +> return "Unbalanced number of calls to notmuch_message_freeze/thaw"; +> case NOTMUCH_STATUS_UNBALANCED_ATOMIC: +> return "Unbalanced number of calls to notmuch_database_begin_atomic/end_atomic"; +> + case NOTMUCH_STATUS_UNSUPPORTED_OPERATION: +> + return "Unsupported operation"; +> default: +> case NOTMUCH_STATUS_LAST_STATUS: +> return "Unknown error status value"; +> @@ -800,6 +802,95 @@ notmuch_database_close (notmuch_database_t *notmuch) +> notmuch->date_range_processor = NULL; +> } +> +> +class NotmuchCompactor : public Xapian::Compactor +> +{ +> +public: +> + virtual void +> + set_status (const std::string &table, const std::string &status) +> + { +> + if (status.length() == 0) +> + printf ("compacting table %s:\n", table.c_str()); +> + else +> + printf (" %s\n", status.c_str()); +> + } + +We're trying to reduce the amount of prints directly from libnotmuch, +not increase. This applies here as well as below. + +> +}; +> + +> +#if HAVE_XAPIAN_COMPACT +> +notmuch_status_t +> +notmuch_database_compact_close (notmuch_database_t *notmuch) +> +{ +> + void *local = talloc_new (NULL); +> + NotmuchCompactor compactor; +> + char *notmuch_path, *xapian_path, *compact_xapian_path, *old_xapian_path; +> + notmuch_status_t ret = NOTMUCH_STATUS_SUCCESS; +> + +> + if (! (notmuch_path = talloc_asprintf (local, "%s/%s", notmuch->path, ".notmuch"))) { +> + ret = NOTMUCH_STATUS_OUT_OF_MEMORY; +> + goto DONE; +> + } +> + +> + if (! (xapian_path = talloc_asprintf (local, "%s/%s", notmuch_path, "xapian"))) { +> + ret = NOTMUCH_STATUS_OUT_OF_MEMORY; +> + goto DONE; +> + } +> + +> + if (! (compact_xapian_path = talloc_asprintf (local, "%s.compact", xapian_path))) { +> + ret = NOTMUCH_STATUS_OUT_OF_MEMORY; +> + goto DONE; +> + } +> + +> + if (! (old_xapian_path = talloc_asprintf (local, "%s.old", xapian_path))) { +> + ret = NOTMUCH_STATUS_OUT_OF_MEMORY; +> + goto DONE; +> + } +> + +> + try { +> + compactor.set_renumber(false); +> + compactor.add_source(xapian_path); +> + compactor.set_destdir(compact_xapian_path); +> + compactor.compact(); +> + +> + if (rename(xapian_path, old_xapian_path)) { +> + fprintf (stderr, "Error moving old database out of the way\n"); +> + ret = NOTMUCH_STATUS_FILE_ERROR; +> + goto DONE; +> + } + +This fails if old_xapian_path exists. + +> + +> + if (rename(compact_xapian_path, xapian_path)) { +> + fprintf (stderr, "Error moving compacted database\n"); +> + ret = NOTMUCH_STATUS_FILE_ERROR; +> + goto DONE; +> + } +> + } catch (Xapian::InvalidArgumentError e) { +> + fprintf (stderr, "Error while compacting: %s", e.get_msg().c_str()); +> + ret = NOTMUCH_STATUS_XAPIAN_EXCEPTION; +> + goto DONE; +> + } +> + +> + fprintf (stderr, "\n"); +> + fprintf (stderr, "\n"); +> + fprintf (stderr, "Old database has been moved to %s", old_xapian_path); +> + fprintf (stderr, "\n"); +> + fprintf (stderr, "To delete run,\n"); +> + fprintf (stderr, "\n"); +> + fprintf (stderr, " rm -R %s\n", old_xapian_path); +> + fprintf (stderr, "\n"); +> + +> + notmuch_database_close(notmuch); +> + +> +DONE: +> + talloc_free(local); + +The database does not get closed on errors. If that's intentional, it +should be documented. + +> + return ret; +> +} +> +#else +> +notmuch_status_t +> +notmuch_database_compact_close (unused (notmuch_database_t *notmuch)) +> +{ +> + fprintf (stderr, "notmuch was compiled against a xapian version lacking compaction support.\n"); +> + return NOTMUCH_STATUS_UNSUPPORTED_OPERATION; +> +} +> +#endif +> + +> void +> notmuch_database_destroy (notmuch_database_t *notmuch) +> { +> diff --git a/lib/notmuch.h b/lib/notmuch.h +> index 998a4ae..e9abd90 100644 +> --- a/lib/notmuch.h +> +++ b/lib/notmuch.h +> @@ -101,6 +101,7 @@ typedef enum _notmuch_status { +> NOTMUCH_STATUS_TAG_TOO_LONG, +> NOTMUCH_STATUS_UNBALANCED_FREEZE_THAW, +> NOTMUCH_STATUS_UNBALANCED_ATOMIC, +> + NOTMUCH_STATUS_UNSUPPORTED_OPERATION, +> +> NOTMUCH_STATUS_LAST_STATUS +> } notmuch_status_t; +> @@ -215,6 +216,20 @@ notmuch_database_open (const char *path, +> void +> notmuch_database_close (notmuch_database_t *database); +> +> +/* Close the given notmuch database and then compact it. + +The implementation first compacts then closes. + +> + * After notmuch_database_close_compact has been called, calls to +> + * other functions on objects derived from this database may either +> + * behave as if the database had not been closed (e.g., if the +> + * required data has been cached) or may fail with a +> + * NOTMUCH_STATUS_XAPIAN_EXCEPTION. +> + * +> + * notmuch_database_close_compact can be called multiple times. Later +> + * calls have no effect. + +This is not true. The Xapian compactor does not require the database to +be open. It will happily open the database read-only and compact the +database again if database has been closed. + +> + */ +> +notmuch_status_t +> +notmuch_database_compact_close (notmuch_database_t *notmuch); + +I'm afraid we really need to re-think the API. + +I see that your CLI 'notmuch compact' command opens the database +read-write, I assume to ensure there are no other writers, so that stuff +doesn't get lost. However if you pass a read-write database that has +been modified, I believe the changes will get lost (as Xapian opens the +database read-only). We shouldn't let the API users shoot themselves in +the foot so easily. + +I think I'd go for something like: + +notmuch_status_t +notmuch_database_compact (const char *path); + +or + +notmuch_status_t +notmuch_database_compact (const char *path, const char *backup); + +which would internally open the database as read-write to ensure no +modifications, compact, and close. If backup != NULL, it would save the +old database there (same mounted file system as the database is a fine +limitation), otherwise remove. + +Even then I'm not completely sure what Xapian WritableDatabase will do +on close when the database has been switched underneath it. But moving +the database after it has been closed has a race condition too. + + +BR, +Jani. + + + +> + +> /* Destroy the notmuch database, closing it if necessary and freeing +> * all associated resources. */ +> void +> -- +> 1.8.1.2 +> +> _______________________________________________ +> notmuch mailing list +> notmuch@notmuchmail.org +> http://notmuchmail.org/mailman/listinfo/notmuch + +-- +Jani