From mboxrd@z Thu Jan 1 00:00:00 1970 From: Georgios Tsalikis Subject: Re: 2 minutes for a reiser4 filesystem to mount. Date: Thu, 29 Oct 2015 14:21:56 +0200 Message-ID: References: <1445636264.2412.0.camel@gmail.com> <1445726364.7642.6.camel@gmail.com> Mime-Version: 1.0 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1445726364.7642.6.camel@gmail.com> Sender: reiserfs-devel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="utf-8"; format="flowed" To: reiserfs-devel@vger.kernel.org On 25/10/2015 01:39 =CF=80=CE=BC, Ivan Shapovalov wrote: > On 2015-10-24 at 22:41 +0300, Georgios Tsalikis wrote: >> On 24/10/2015 01:58 =CF=80=CE=BC, Ivan Shapovalov wrote: >>>> 24 =D0=BE=D0=BA=D1=82. 2015 =D0=B3., =D0=B2 1:06, Georgios Tsaliki= s >>> .gr> =D0=BD=D0=B0=D0=BF=D0=B8=D1=81=D0=B0=D0=BB(=D0=B0): >>>> >>>>> On 24/10/2015 12:37 =CF=80=CE=BC, Ivan Shapovalov wrote: >>>>>> On 2015-10-22 at 20:38 +0300, Georgios Tsalikis wrote: >>>>>> The filesystem is 1.7GB large, lies in a GPT patition and is >>>>>> formated >>>>>> with -o node=3Dnode41 without any other override. The kernel is >>>>>> 4.2.3 >>>>>> with >>>>>> the 4.2.2 patch. >>>>>> I tried the same on a 250MB partition and it mounts >>>>>> instantly. dmesg >>>>>> shows nothing special >>>>>> Any ideas? Thanks in advance. :) >>>>> Hello, >>>>> >>>>> try "dont_load_bitmap" in mount options. However, this is >>>>> anyway very >>>>> strange for a ~2GB partition... >>>> I am sorry, did i write 1.7GB? I meant 1.7TB... i am old and such >>>> figures dont fit my mind easily! >>> Ah, so it's 1.7 TB? Then it's not unusual at all. Indeed, try >>> mounting with `-o dont_load_bitmap`. >>> >> I did so and it worked. Thank you. But what does that option do? > This option tells reiser4 to load bitmap blocks on demand, and not al= l > at once at filesystem mount time. Does this mean using this option means a penalty? Maybe in some cases=20 (servers etc) it is worth waiting the fs to mount? > > The bitmap is how reiser4 stores information about which on-disk bloc= ks > are allocated and which are free (one bit corresponds to one block, > hence the name). > > The 2TiB filesystem has 2*1024^4 / 4096 =3D 536870912 blocks, which t= ake > 536870912 / (8*4096) =3D 16384 bitmap blocks, so it takes 120/16384 ~= 7ms > to load one block, which is not that unusual (given that the bitmap > loading doesn't seem to be optimized too well: each block is read in = a > separate request). > >> And which are the other options and their function? > I'm afraid that the full list of reiser4 options can only be found in > code (file init_super.c, functions push_sb_field_opts() and > reiser4_init_super_data(). > -- To unsubscribe from this list: send the line "unsubscribe reiserfs-deve= l" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html