[OE-core] [RFC 1/2] IMAGE_ROOTFS_SIZE Cleanup
Joshua Lock
josh at linux.intel.com
Thu May 26 21:31:52 UTC 2011
On Thu, 2011-05-26 at 14:15 -0700, Saul Wold wrote:
> On 05/26/2011 02:13 PM, Joshua Lock wrote:
> > On Thu, 2011-05-26 at 14:03 -0700, Darren Hart wrote:
> >>
> >> On 05/26/2011 02:01 PM, Joshua Lock wrote:
> >>> On Thu, 2011-05-26 at 13:55 -0700, Darren Hart wrote:
> >>>>
> >>>> On 05/26/2011 12:54 PM, Joshua Lock wrote:
> >>>>> On Thu, 2011-05-26 at 11:28 -0700, Saul Wold wrote:
> >>>>>> On 05/26/2011 11:04 AM, Joshua Lock wrote:
> >>>>>>> On Mon, 2011-05-23 at 23:38 -0700, Saul Wold wrote:
> >>>>>>>> This basic cleanup removes the _ext2/3 overrides from places they
> >>>>>>>> no longer belong since they did not allow further overrides. In doing
> >>>>>>>> this the core-image-minimal* recipes can now set a reasonably small
> >>>>>>>> rootfs so that it's a realistic size for minimal.
> >>>>>>>
> >>>>>>> Awesome. Thanks for tackling this!
> >>>>>>>
> >>>>>>> Few questions below.
> >>>>>>>
> >>>>>>>>
> >>>>>>>> The new default for minimal is 8M and will be adujsted upward by the
> >>>>>>>> IMAGE_OVERHEAD_FACTOR (of 1.2).
> >>>>>>>>
> >>>>>>>> This fixes the ROOTFS_SIZE usage in the IMAGE_CMD_<fstype> code
> >>>>>>>>
> >>>>>>>> Signed-off-by: Saul Wold<sgw at linux.intel.com>
> >>>>>>>> ---
> >>>>>>>> meta/classes/image_types.bbclass | 7 +++++--
> >>>>>>>> meta/conf/distro/include/default-distrovars.inc | 2 --
> >>>>>>>> meta/conf/machine/include/qemu.inc | 2 --
> >>>>>>>> .../images/core-image-minimal-initramfs.bb | 2 ++
> >>>>>>>> meta/recipes-core/images/core-image-minimal.bb | 2 ++
> >>>>>>>> 5 files changed, 9 insertions(+), 6 deletions(-)
> >>>>>>>>
> >>>>>>>> diff --git a/meta/classes/image_types.bbclass b/meta/classes/image_types.bbclass
> >>>>>>>> index ec0cafd..69f859e 100644
> >>>>>>>> --- a/meta/classes/image_types.bbclass
> >>>>>>>> +++ b/meta/classes/image_types.bbclass
> >>>>>>>> @@ -21,22 +21,25 @@ runimagecmd () {
> >>>>>>>> }
> >>>>>>>>
> >>>>>>>> IMAGE_CMD_jffs2 = "mkfs.jffs2 --root=${IMAGE_ROOTFS} --faketime --output=${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.jffs2 ${EXTRA_IMAGECMD}"
> >>>>>>>> +
> >>>>>>>> IMAGE_CMD_cramfs = "mkcramfs ${IMAGE_ROOTFS} ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.cramfs ${EXTRA_IMAGECMD}"
> >>>>>>>> +
> >>>>>>>> IMAGE_CMD_ext2 = "genext2fs -b $ROOTFS_SIZE -d ${IMAGE_ROOTFS} ${EXTRA_IMAGECMD} ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.ext2"
> >>>>>>>> IMAGE_CMD_ext2.gz () {
> >>>>>>>> rm -rf ${DEPLOY_DIR_IMAGE}/tmp.gz&& mkdir ${DEPLOY_DIR_IMAGE}/tmp.gz
> >>>>>>>> - genext2fs -b ${IMAGE_ROOTFS_SIZE} -d ${IMAGE_ROOTFS} ${EXTRA_IMAGECMD} ${DEPLOY_DIR_IMAGE}/tmp.gz/${IMAGE_NAME}.rootfs.ext2
> >>>>>>>> + genext2fs -b $ROOTFS_SIZE -d ${IMAGE_ROOTFS} ${EXTRA_IMAGECMD} ${DEPLOY_DIR_IMAGE}/tmp.gz/${IMAGE_NAME}.rootfs.ext2
> >>>>>>>> gzip -f -9 ${DEPLOY_DIR_IMAGE}/tmp.gz/${IMAGE_NAME}.rootfs.ext2
> >>>>>>>> mv ${DEPLOY_DIR_IMAGE}/tmp.gz/${IMAGE_NAME}.rootfs.ext2.gz ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.ext2.gz
> >>>>>>>> rmdir ${DEPLOY_DIR_IMAGE}/tmp.gz
> >>>>>>>> }
> >>>>>>>> +
> >>>>>>>> IMAGE_CMD_ext3 () {
> >>>>>>>> genext2fs -b $ROOTFS_SIZE -d ${IMAGE_ROOTFS} ${EXTRA_IMAGECMD} ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.ext3
> >>>>>>>> tune2fs -j ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.ext3
> >>>>>>>> }
> >>>>>>>> IMAGE_CMD_ext3.gz () {
> >>>>>>>> rm -rf ${DEPLOY_DIR_IMAGE}/tmp.gz&& mkdir ${DEPLOY_DIR_IMAGE}/tmp.gz
> >>>>>>>> - genext2fs -b ${IMAGE_ROOTFS_SIZE} -d ${IMAGE_ROOTFS} ${EXTRA_IMAGECMD} ${DEPLOY_DIR_IMAGE}/tmp.gz/${IMAGE_NAME}.rootfs.ext3
> >>>>>>>> + genext2fs -b $ROOTFS_SIZE -d ${IMAGE_ROOTFS} ${EXTRA_IMAGECMD} ${DEPLOY_DIR_IMAGE}/tmp.gz/${IMAGE_NAME}.rootfs.ext3
> >>>>>>>> tune2fs -j ${DEPLOY_DIR_IMAGE}/tmp.gz/${IMAGE_NAME}.rootfs.ext3
> >>>>>>>> gzip -f -9 ${DEPLOY_DIR_IMAGE}/tmp.gz/${IMAGE_NAME}.rootfs.ext3
> >>>>>>>> mv ${DEPLOY_DIR_IMAGE}/tmp.gz/${IMAGE_NAME}.rootfs.ext3.gz ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.ext3.gz
> >>>>>>>> diff --git a/meta/conf/distro/include/default-distrovars.inc b/meta/conf/distro/include/default-distrovars.inc
> >>>>>>>> index 1aa45c8..4b68a0a 100644
> >>>>>>>> --- a/meta/conf/distro/include/default-distrovars.inc
> >>>>>>>> +++ b/meta/conf/distro/include/default-distrovars.inc
> >>>>>>>> @@ -1,7 +1,5 @@
> >>>>>>>> QA_LOGFILE = "${TMPDIR}/qa.log"
> >>>>>>>>
> >>>>>>>> -IMAGE_ROOTFS_SIZE_ext2 ?= "131072"
> >>>>>>>> -
> >>>>>>>> OEINCLUDELOGS ?= "yes"
> >>>>>>>> KERNEL_CONSOLE ?= "ttyS0"
> >>>>>>>>
> >>>>>>>> diff --git a/meta/conf/machine/include/qemu.inc b/meta/conf/machine/include/qemu.inc
> >>>>>>>> index 4122a88..9ef242f 100644
> >>>>>>>> --- a/meta/conf/machine/include/qemu.inc
> >>>>>>>> +++ b/meta/conf/machine/include/qemu.inc
> >>>>>>>> @@ -6,8 +6,6 @@ MACHINE_FEATURES = "kernel26 apm alsa pcmcia bluetooth irda usbgadget screen"
> >>>>>>>> IMAGE_FSTYPES ?= "tar.bz2 ext3"
> >>>>>>>>
> >>>>>>>> ROOT_FLASH_SIZE = "280"
> >>>>>>>> -IMAGE_ROOTFS_SIZE_ext2 ?= "280000"
> >>>>>>>> -IMAGE_ROOTFS_SIZE_ext3 ?= "280000"
> >>>>>>>>
> >>>>>>>> # Don't include kernels in standard images
> >>>>>>>> RDEPENDS_kernel-base = ""
> >>>>>>>> diff --git a/meta/recipes-core/images/core-image-minimal-initramfs.bb b/meta/recipes-core/images/core-image-minimal-initramfs.bb
> >>>>>>>> index 21aaa6c..3246d5c 100644
> >>>>>>>> --- a/meta/recipes-core/images/core-image-minimal-initramfs.bb
> >>>>>>>> +++ b/meta/recipes-core/images/core-image-minimal-initramfs.bb
> >>>>>>>> @@ -8,3 +8,5 @@ IMAGE_LINGUAS = ""
> >>>>>>>> LICENSE = "MIT"
> >>>>>>>>
> >>>>>>>> inherit core-image
> >>>>>>>> +
> >>>>>>>> +IMAGE_ROOTFS_SIZE = "8192"
> >>>>>>>
> >>>>>>> I'm not really sure about this, an initramfs that's the same size as a
> >>>>>>> more fully featured rootfs?
> >>>>>>>
> >>>>>> That may be, then we need to increase the size slightly, but this will
> >>>>>> trigger the correct behavior of actual size * IMAGE_OVERHEAD_FACTOR,
> >>>>>> rather than the 64M which would be the default, this was to ensure it
> >>>>>> could get smaller. I don't have a current initramfs size, I will build
> >>>>>> and verify.
> >>>>>>
> >>>>>>
> >>>>>>>> diff --git a/meta/recipes-core/images/core-image-minimal.bb b/meta/recipes-core/images/core-image-minimal.bb
> >>>>>>>> index aa00e67..743e121 100644
> >>>>>>>> --- a/meta/recipes-core/images/core-image-minimal.bb
> >>>>>>>> +++ b/meta/recipes-core/images/core-image-minimal.bb
> >>>>>>>> @@ -9,5 +9,7 @@ LICENSE = "MIT"
> >>>>>>>>
> >>>>>>>> inherit core-image
> >>>>>>>>
> >>>>>>>> +IMAGE_ROOTFS_SIZE = "8192"
> >>>>>>>> +
> >>>>>>>
> >>>>>>> In your cover letter you stated that the minimal image is currently
> >>>>>>> 9.9M, which means we *need* the overhead to contain the entire image
> >>>>>>> contents. Correct? That seems a little unwise.
> >>>>>>>
> >>>>>> Right, that's currently, we want to see the image get smaller even, so
> >>>>>> the 8M is an appropriate setting. Currently the actual ext3 image is
> >>>>>> 13M with 10M of contents.
> >>>>>>
> >>>>>> So are you suggested that the 8M size is unwise or the overhead, not
> >>>>>> sure I am catching your meaning here.
> >>>>>
> >>>>> I'm just nervous about relying on the overhead, what if someone sets it
> >>>>> lower and then the image doesn't fit?
> >>>>>
> >>>>> Having the goal of a smaller minimal image is good but in my opinion we
> >>>>> should adjust the rootfs size when the image is smaller, not before.
> >>>>
> >>>> Every argument I've heard in favor of the IMAGE_OVERHEAD was centered
> >>>> around ensuring there is enough space for the user to actually use the
> >>>> system after it was installed and booted. Using this single metric to
> >>>> try and both make up for oversized images and provide space for user
> >>>> data seems like to cause maintenance issues going forward.
> >>>>
> >>>> While our goal should be to reduce the image size, the default image
> >>>> size in the recipes should default to the largest of the images built
> >>>> for the supported machines. The overhead should be used strictly for
> >>>> user data.
> >>>>
> >>>
> >>> So it turns out that if IMAGE_ROOTFS is smaller than the contents the
> >>> size of the contents is used. Once this if test has been performed the
> >>> overhead factor is applied.
> >>
> >> Ah Good!
> >>
> >>>
> >>> I found this to be a tad confusing (hence all the back and forth here)
> >>> so have filed a documentation bug about it:
> >>> http://bugzilla.pokylinux.org/show_bug.cgi?id=1110
> >>>
> >>> Maybe we can have some comments in the code near where those variables
> >>> are set too?
> >>>
> >>
> >> Yeah, this wasn't clear to me either. And my question in 2/2 still
> >> stands - what is the goal of the overhead factor?
> >>
> >
> > My understanding is that it's for system overhead such as postinstalls
> > whereas ROOTFS_IMAGE_EXTRA_SPACE is for user and data space that you
> > want above the standard image size.
> >
> Correct
>
> > So if you want to ensure all of your images have 2GB space for data
> > you'd set the ROOTFS_IMAGE_EXTRA_SPACE to 2GB.
> >
> That's one way, another is if you want all your images to be 2G
> including the core contents set ROOTFS_IMAGE_SIZE to 2G and the images
> will all be 2G (remember to set in K, since we don't parse the M or G).
We probably should though. Shall I file a feature request? :-)
Cheers,
Joshua
--
Joshua Lock
Yocto Project Build Monkey
Intel Open Source Technology Centre
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