No space left on device (again)

No space left on device (again)

[Marcus Sundman]

Hi

I get "No space left on device" and it is unclear why:

> # df -h|grep sda3
> /dev/sda3       413G  368G   45G  90% /home
> # btrfs filesystem show /dev/sda3
> Label: 'home'  uuid: 46279061-51f4-40c2-afd0-61d6faab7f60
>     Total devices 1 FS bytes used 371.11GB
>     devid    1 size 412.54GB used 412.54GB path /dev/sda3
>
> Btrfs v0.20-rc1
> # btrfs filesystem df /home
> Data: total=410.52GB, used=369.61GB
> System: total=4.00MB, used=64.00KB
> Metadata: total=2.01GB, used=1.50GB
> #

So, 'data' and 'metadata' seem to be fine(?), but 'system' is a bit low. 
Is that it? If so, can I do something about it? Or should I look 
somewhere else?

I really wish I could get a warning before running out of disk space, 
instead of everything breaking suddenly when there seems to be lots and 
lots of space left.

- Marcus

Re: No space left on device (again)

[Jim Salter]

370GB of 410GB used isn't really "fine", it's over 90% usage.

That said, I'd be interested to know why btrfs fi show /dev/sda3 shows 
412.54G used, but btrfs fi df /home shows 379G used...



On 02/25/2014 11:49 AM, Marcus Sundman wrote:
> Hi
>
> I get "No space left on device" and it is unclear why:
>
>> # df -h|grep sda3
>> /dev/sda3       413G  368G   45G  90% /home
>> # btrfs filesystem show /dev/sda3
>> Label: 'home'  uuid: 46279061-51f4-40c2-afd0-61d6faab7f60
>>     Total devices 1 FS bytes used 371.11GB
>>     devid    1 size 412.54GB used 412.54GB path /dev/sda3
>>
>> Btrfs v0.20-rc1
>> # btrfs filesystem df /home
>> Data: total=410.52GB, used=369.61GB
>> System: total=4.00MB, used=64.00KB
>> Metadata: total=2.01GB, used=1.50GB
>> #
>
> So, 'data' and 'metadata' seem to be fine(?), but 'system' is a bit 
> low. Is that it? If so, can I do something about it? Or should I look 
> somewhere else?
>
> I really wish I could get a warning before running out of disk space, 
> instead of everything breaking suddenly when there seems to be lots 
> and lots of space left.
>
> - Marcus
>
> -- 
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: No space left on device (again)

[Marcus Sundman]

On 25.02.2014 20:05, Jim Salter wrote:
> 370GB of 410GB used isn't really "fine", it's over 90% usage.

Still, 45 gigs should be free there. If those 45 gigs aren't really 
there then it shouldn't say they are there, imho.

> That said, I'd be interested to know why btrfs fi show /dev/sda3 shows 
> 412.54G used, but btrfs fi df /home shows 379G used...

The former also says "bytes used 371.11GB" and there's not *that* much 
difference between "371.11" and "369.61" gigs. The devid line seems to 
always say "412.54GB used 412.54GB" no matter how much is actually in use.
I have no idea what these numbers actually mean.

> On 02/25/2014 11:49 AM, Marcus Sundman wrote:
>> Hi
>>
>> I get "No space left on device" and it is unclear why:
>>
>>> # df -h|grep sda3
>>> /dev/sda3       413G  368G   45G  90% /home
>>> # btrfs filesystem show /dev/sda3
>>> Label: 'home'  uuid: 46279061-51f4-40c2-afd0-61d6faab7f60
>>>     Total devices 1 FS bytes used 371.11GB
>>>     devid    1 size 412.54GB used 412.54GB path /dev/sda3
>>>
>>> Btrfs v0.20-rc1
>>> # btrfs filesystem df /home
>>> Data: total=410.52GB, used=369.61GB
>>> System: total=4.00MB, used=64.00KB
>>> Metadata: total=2.01GB, used=1.50GB
>>> #
>>
>> So, 'data' and 'metadata' seem to be fine(?), but 'system' is a bit 
>> low. Is that it? If so, can I do something about it? Or should I look 
>> somewhere else?
>>
>> I really wish I could get a warning before running out of disk space, 
>> instead of everything breaking suddenly when there seems to be lots 
>> and lots of space left.
>>
>> - Marcus
>>
>> -- 
>> To unsubscribe from this list: send the line "unsubscribe 
>> linux-btrfs" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
> -- 
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: No space left on device (again)

[Hugo Mills]

[-- Attachment #1: Type: text/plain, Size: 2052 bytes --]

On Tue, Feb 25, 2014 at 01:05:51PM -0500, Jim Salter wrote:
> 370GB of 410GB used isn't really "fine", it's over 90% usage.
> 
> That said, I'd be interested to know why btrfs fi show /dev/sda3
> shows 412.54G used, but btrfs fi df /home shows 379G used...

   This is an FAQ...

   btrfs fi show tells you how much is allocated out of the available
pool on each disk. btrfs fi df then shows how much of that allocated
space (in each category) is used.

   The problem here is also in the FAQ: the metadata is close to full
-- typically something like 500-750 MiB of headroom is needed in
metadata. The FS can't allocate more metadata because it's allocated
everything already (total=used in btrfs fi show), so the solution is
to do a filtered balance:

btrfs balance start -dusage=5 /mountpoint

   Hugo.

> 
> On 02/25/2014 11:49 AM, Marcus Sundman wrote:
> >Hi
> >
> >I get "No space left on device" and it is unclear why:
> >
> >># df -h|grep sda3
> >>/dev/sda3       413G  368G   45G  90% /home
> >># btrfs filesystem show /dev/sda3
> >>Label: 'home'  uuid: 46279061-51f4-40c2-afd0-61d6faab7f60
> >>    Total devices 1 FS bytes used 371.11GB
> >>    devid    1 size 412.54GB used 412.54GB path /dev/sda3
> >>
> >>Btrfs v0.20-rc1
> >># btrfs filesystem df /home
> >>Data: total=410.52GB, used=369.61GB
> >>System: total=4.00MB, used=64.00KB
> >>Metadata: total=2.01GB, used=1.50GB
> >>#
> >
> >So, 'data' and 'metadata' seem to be fine(?), but 'system' is a
> >bit low. Is that it? If so, can I do something about it? Or should
> >I look somewhere else?
> >
> >I really wish I could get a warning before running out of disk
> >space, instead of everything breaking suddenly when there seems to
> >be lots and lots of space left.
> >
> >- Marcus
> >

-- 
=== Hugo Mills: hugo@... carfax.org.uk | darksatanic.net | lug.org.uk ===
  PGP key: 65E74AC0 from wwwkeys.eu.pgp.net or http://www.carfax.org.uk
    --- Jazz is the sort of music where no-one plays anything the ---    
                             same way once.                              

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Re: No space left on device (again)

[Marcus Sundman]

On 25.02.2014 22:19, Hugo Mills wrote:
> On Tue, Feb 25, 2014 at 01:05:51PM -0500, Jim Salter wrote:
>> 370GB of 410GB used isn't really "fine", it's over 90% usage.
>>
>> That said, I'd be interested to know why btrfs fi show /dev/sda3
>> shows 412.54G used, but btrfs fi df /home shows 379G used...
>     This is an FAQ...
>
>     btrfs fi show tells you how much is allocated out of the available
> pool on each disk. btrfs fi df then shows how much of that allocated
> space (in each category) is used.

What is the difference between the "used 371.11GB" and the "used 
412.54GB" displayed by "btrfs fi show"?

>     The problem here is also in the FAQ: the metadata is close to full
> -- typically something like 500-750 MiB of headroom is needed in
> metadata. The FS can't allocate more metadata because it's allocated
> everything already (total=used in btrfs fi show), so the solution is
> to do a filtered balance:
>
> btrfs balance start -dusage=5 /mountpoint

Of course that was the first thing I tried, and it didn't help *at* *all*:

> # btrfs filesystem balance start -dusage=5 /home
> Done, had to relocate 0 out of 415 chunks
> #

... and it really didn't free anything.

>> On 02/25/2014 11:49 AM, Marcus Sundman wrote:
>>> Hi
>>>
>>> I get "No space left on device" and it is unclear why:
>>>
>>>> # df -h|grep sda3
>>>> /dev/sda3       413G  368G   45G  90% /home
>>>> # btrfs filesystem show /dev/sda3
>>>> Label: 'home'  uuid: 46279061-51f4-40c2-afd0-61d6faab7f60
>>>>     Total devices 1 FS bytes used 371.11GB
>>>>     devid    1 size 412.54GB used 412.54GB path /dev/sda3
>>>>
>>>> Btrfs v0.20-rc1
>>>> # btrfs filesystem df /home
>>>> Data: total=410.52GB, used=369.61GB
>>>> System: total=4.00MB, used=64.00KB
>>>> Metadata: total=2.01GB, used=1.50GB
>>>> #
>>> So, 'data' and 'metadata' seem to be fine(?), but 'system' is a
>>> bit low. Is that it? If so, can I do something about it? Or should
>>> I look somewhere else?
>>>
>>> I really wish I could get a warning before running out of disk
>>> space, instead of everything breaking suddenly when there seems to
>>> be lots and lots of space left.
>>>
>>> - Marcus
>>>

Re: No space left on device (again)

[Josef Bacik]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 02/25/2014 03:27 PM, Marcus Sundman wrote:
> On 25.02.2014 22:19, Hugo Mills wrote:
>> On Tue, Feb 25, 2014 at 01:05:51PM -0500, Jim Salter wrote:
>>> 370GB of 410GB used isn't really "fine", it's over 90% usage.
>>> 
>>> That said, I'd be interested to know why btrfs fi show
>>> /dev/sda3 shows 412.54G used, but btrfs fi df /home shows 379G
>>> used...
>> This is an FAQ...
>> 
>> btrfs fi show tells you how much is allocated out of the
>> available pool on each disk. btrfs fi df then shows how much of
>> that allocated space (in each category) is used.
> 
> What is the difference between the "used 371.11GB" and the "used 
> 412.54GB" displayed by "btrfs fi show"?
> 
>> The problem here is also in the FAQ: the metadata is close to
>> full -- typically something like 500-750 MiB of headroom is
>> needed in metadata. The FS can't allocate more metadata because
>> it's allocated everything already (total=used in btrfs fi show),
>> so the solution is to do a filtered balance:
>> 
>> btrfs balance start -dusage=5 /mountpoint
> 
> Of course that was the first thing I tried, and it didn't help *at*
> *all*:
> 

The -dusage=<number> is a means to an end, so if that doesn't work try
a larger number, up to 100.  Really once you pass 50 and it's not
working then it's time to just do a balance.  The next thing is to use
compression (too late for this option really) or add another disk.
Thanks,

Josef

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Re: No space left on device (again)

[cwillu]

Try btrfs filesystem balance start -dusage=15 /home, and gradually
increase it until you see it relocate at least one chunk.

On Tue, Feb 25, 2014 at 2:27 PM, Marcus Sundman <sundman@iki.fi> wrote:
> On 25.02.2014 22:19, Hugo Mills wrote:
>>
>> On Tue, Feb 25, 2014 at 01:05:51PM -0500, Jim Salter wrote:
>>>
>>> 370GB of 410GB used isn't really "fine", it's over 90% usage.
>>>
>>> That said, I'd be interested to know why btrfs fi show /dev/sda3
>>> shows 412.54G used, but btrfs fi df /home shows 379G used...
>>
>>     This is an FAQ...
>>
>>     btrfs fi show tells you how much is allocated out of the available
>> pool on each disk. btrfs fi df then shows how much of that allocated
>> space (in each category) is used.
>
>
> What is the difference between the "used 371.11GB" and the "used 412.54GB"
> displayed by "btrfs fi show"?
>
>
>>     The problem here is also in the FAQ: the metadata is close to full
>> -- typically something like 500-750 MiB of headroom is needed in
>> metadata. The FS can't allocate more metadata because it's allocated
>> everything already (total=used in btrfs fi show), so the solution is
>> to do a filtered balance:
>>
>> btrfs balance start -dusage=5 /mountpoint
>
>
> Of course that was the first thing I tried, and it didn't help *at* *all*:
>
>> # btrfs filesystem balance start -dusage=5 /home
>> Done, had to relocate 0 out of 415 chunks
>> #
>
>
> ... and it really didn't free anything.
>
>
>>> On 02/25/2014 11:49 AM, Marcus Sundman wrote:
>>>>
>>>> Hi
>>>>
>>>> I get "No space left on device" and it is unclear why:
>>>>
>>>>> # df -h|grep sda3
>>>>> /dev/sda3       413G  368G   45G  90% /home
>>>>> # btrfs filesystem show /dev/sda3
>>>>> Label: 'home'  uuid: 46279061-51f4-40c2-afd0-61d6faab7f60
>>>>>     Total devices 1 FS bytes used 371.11GB
>>>>>     devid    1 size 412.54GB used 412.54GB path /dev/sda3
>>>>>
>>>>> Btrfs v0.20-rc1
>>>>> # btrfs filesystem df /home
>>>>> Data: total=410.52GB, used=369.61GB
>>>>> System: total=4.00MB, used=64.00KB
>>>>> Metadata: total=2.01GB, used=1.50GB
>>>>> #
>>>>
>>>> So, 'data' and 'metadata' seem to be fine(?), but 'system' is a
>>>> bit low. Is that it? If so, can I do something about it? Or should
>>>> I look somewhere else?
>>>>
>>>> I really wish I could get a warning before running out of disk
>>>> space, instead of everything breaking suddenly when there seems to
>>>> be lots and lots of space left.
>>>>
>>>> - Marcus
>>>>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: No space left on device (again)

[Hugo Mills]

[-- Attachment #1: Type: text/plain, Size: 3284 bytes --]

On Tue, Feb 25, 2014 at 10:27:58PM +0200, Marcus Sundman wrote:
> On 25.02.2014 22:19, Hugo Mills wrote:
> >On Tue, Feb 25, 2014 at 01:05:51PM -0500, Jim Salter wrote:
> >>370GB of 410GB used isn't really "fine", it's over 90% usage.
> >>
> >>That said, I'd be interested to know why btrfs fi show /dev/sda3
> >>shows 412.54G used, but btrfs fi df /home shows 379G used...
> >    This is an FAQ...
> >
> >    btrfs fi show tells you how much is allocated out of the available
> >pool on each disk. btrfs fi df then shows how much of that allocated
> >space (in each category) is used.
> 
> What is the difference between the "used 371.11GB" and the "used
> 412.54GB" displayed by "btrfs fi show"?

   The first and smaller value is (in this case) the sum of all the
"used" values in the output of btrfs fi df. The second is the total
amount of raw disk space that has been allocated. (Yes, this is a bit
of a mess -- there's been discussions recently about improving the
output).

> >    The problem here is also in the FAQ: the metadata is close to full
> >-- typically something like 500-750 MiB of headroom is needed in
> >metadata. The FS can't allocate more metadata because it's allocated
> >everything already (total=used in btrfs fi show), so the solution is
> >to do a filtered balance:
> >
> >btrfs balance start -dusage=5 /mountpoint
> 
> Of course that was the first thing I tried, and it didn't help *at* *all*:
> 
> ># btrfs filesystem balance start -dusage=5 /home
> >Done, had to relocate 0 out of 415 chunks
> >#
> 
> ... and it really didn't free anything.

   OK, so crank up the number to 10 and try again. If that still moves
nothing, then increase again until it frees up something. With an FS
at 90% full or so, particularly if it's seen heavy use, the chances
are reasonable that all of the chunks are over 5% full, so putting the
value up will eventually get to the point of moving at least one
chunk, which should be all that's needed at this point.

   Hugo.

> >>On 02/25/2014 11:49 AM, Marcus Sundman wrote:
> >>>Hi
> >>>
> >>>I get "No space left on device" and it is unclear why:
> >>>
> >>>># df -h|grep sda3
> >>>>/dev/sda3       413G  368G   45G  90% /home
> >>>># btrfs filesystem show /dev/sda3
> >>>>Label: 'home'  uuid: 46279061-51f4-40c2-afd0-61d6faab7f60
> >>>>    Total devices 1 FS bytes used 371.11GB
> >>>>    devid    1 size 412.54GB used 412.54GB path /dev/sda3
> >>>>
> >>>>Btrfs v0.20-rc1
> >>>># btrfs filesystem df /home
> >>>>Data: total=410.52GB, used=369.61GB
> >>>>System: total=4.00MB, used=64.00KB
> >>>>Metadata: total=2.01GB, used=1.50GB
> >>>>#
> >>>So, 'data' and 'metadata' seem to be fine(?), but 'system' is a
> >>>bit low. Is that it? If so, can I do something about it? Or should
> >>>I look somewhere else?
> >>>
> >>>I really wish I could get a warning before running out of disk
> >>>space, instead of everything breaking suddenly when there seems to
> >>>be lots and lots of space left.
> >>>
> >>>- Marcus
> >>>
> 

-- 
=== Hugo Mills: hugo@... carfax.org.uk | darksatanic.net | lug.org.uk ===
  PGP key: 65E74AC0 from wwwkeys.eu.pgp.net or http://www.carfax.org.uk
    --- Jazz is the sort of music where no-one plays anything the ---    
                             same way once.                              

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Re: No space left on device (again)

[Sander]

Josef Bacik wrote (ao):
> The -dusage=<number> is a means to an end, so if that doesn't work try
> a larger number, up to 100.  Really once you pass 50 and it's not
> working then it's time to just do a balance.  The next thing is to use
> compression (too late for this option really) or add another disk.

btrfs filesystem defragment -vrc /home/

would apply compression to all files, no?

	Sander

Re: No space left on device (again)

[Marcus Sundman]

On 25.02.2014 22:30, Josef Bacik wrote:
> On 02/25/2014 03:27 PM, Marcus Sundman wrote:
>> On 25.02.2014 22:19, Hugo Mills wrote:
>>> On Tue, Feb 25, 2014 at 01:05:51PM -0500, Jim Salter wrote:
>>>> 370GB of 410GB used isn't really "fine", it's over 90% usage.
>>>>
>>>> That said, I'd be interested to know why btrfs fi show
>>>> /dev/sda3 shows 412.54G used, but btrfs fi df /home shows 379G
>>>> used...
>>> This is an FAQ...
>>>
>>> btrfs fi show tells you how much is allocated out of the
>>> available pool on each disk. btrfs fi df then shows how much of
>>> that allocated space (in each category) is used.
>> What is the difference between the "used 371.11GB" and the "used
>> 412.54GB" displayed by "btrfs fi show"?
>>
>>> The problem here is also in the FAQ: the metadata is close to
>>> full -- typically something like 500-750 MiB of headroom is
>>> needed in metadata. The FS can't allocate more metadata because
>>> it's allocated everything already (total=used in btrfs fi show),
>>> so the solution is to do a filtered balance:
>>>
>>> btrfs balance start -dusage=5 /mountpoint
>> Of course that was the first thing I tried, and it didn't help *at*
>> *all*:
>>
> The -dusage=<number> is a means to an end, so if that doesn't work try
> a larger number, up to 100.  Really once you pass 50 and it's not
> working then it's time to just do a balance.  The next thing is to use
> compression (too late for this option really) or add another disk.

So it relocates some chunks. What will that do? Does it mean I can now 
use the remaining 45 GB? Or will it run out of "disk space" again after 
using a gig or two?
If it's the allocated metadata space that is the problem then how can I 
pre-allocate more of it so it won't run out of it?


- Marcus

Re: No space left on device (again)

[Josef Bacik]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 02/26/2014 07:16 PM, Marcus Sundman wrote:
> On 25.02.2014 22:30, Josef Bacik wrote:
>> On 02/25/2014 03:27 PM, Marcus Sundman wrote:
>>> On 25.02.2014 22:19, Hugo Mills wrote:
>>>> On Tue, Feb 25, 2014 at 01:05:51PM -0500, Jim Salter wrote:
>>>>> 370GB of 410GB used isn't really "fine", it's over 90%
>>>>> usage.
>>>>> 
>>>>> That said, I'd be interested to know why btrfs fi show 
>>>>> /dev/sda3 shows 412.54G used, but btrfs fi df /home shows
>>>>> 379G used...
>>>> This is an FAQ...
>>>> 
>>>> btrfs fi show tells you how much is allocated out of the 
>>>> available pool on each disk. btrfs fi df then shows how much
>>>> of that allocated space (in each category) is used.
>>> What is the difference between the "used 371.11GB" and the
>>> "used 412.54GB" displayed by "btrfs fi show"?
>>> 
>>>> The problem here is also in the FAQ: the metadata is close
>>>> to full -- typically something like 500-750 MiB of headroom
>>>> is needed in metadata. The FS can't allocate more metadata
>>>> because it's allocated everything already (total=used in
>>>> btrfs fi show), so the solution is to do a filtered balance:
>>>> 
>>>> btrfs balance start -dusage=5 /mountpoint
>>> Of course that was the first thing I tried, and it didn't help
>>> *at* *all*:
>>> 
>> The -dusage=<number> is a means to an end, so if that doesn't
>> work try a larger number, up to 100.  Really once you pass 50 and
>> it's not working then it's time to just do a balance.  The next
>> thing is to use compression (too late for this option really) or
>> add another disk.
> 
> So it relocates some chunks. What will that do? Does it mean I can
> now use the remaining 45 GB? Or will it run out of "disk space"
> again after using a gig or two? If it's the allocated metadata
> space that is the problem then how can I pre-allocate more of it so
> it won't run out of it?
> 
> 

It will allocate more as it sees fit, there is a metadata_ratio=N
option which lets you force it to allocate a metadata chunk for every
N data chunk allocations, but that shouldn't be needed in this case.
What does btrfs fi df and btrfs show look like now?  Thanks,

Josef
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Re: No space left on device (again)

[Hugo Mills]

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On Thu, Feb 27, 2014 at 02:16:07AM +0200, Marcus Sundman wrote:
> On 25.02.2014 22:30, Josef Bacik wrote:
> >On 02/25/2014 03:27 PM, Marcus Sundman wrote:
> >>On 25.02.2014 22:19, Hugo Mills wrote:
> >>>On Tue, Feb 25, 2014 at 01:05:51PM -0500, Jim Salter wrote:
> >>>>370GB of 410GB used isn't really "fine", it's over 90% usage.
> >>>>
> >>>>That said, I'd be interested to know why btrfs fi show
> >>>>/dev/sda3 shows 412.54G used, but btrfs fi df /home shows 379G
> >>>>used...
> >>>This is an FAQ...
> >>>
> >>>btrfs fi show tells you how much is allocated out of the
> >>>available pool on each disk. btrfs fi df then shows how much of
> >>>that allocated space (in each category) is used.
> >>What is the difference between the "used 371.11GB" and the "used
> >>412.54GB" displayed by "btrfs fi show"?
> >>
> >>>The problem here is also in the FAQ: the metadata is close to
> >>>full -- typically something like 500-750 MiB of headroom is
> >>>needed in metadata. The FS can't allocate more metadata because
> >>>it's allocated everything already (total=used in btrfs fi show),
> >>>so the solution is to do a filtered balance:
> >>>
> >>>btrfs balance start -dusage=5 /mountpoint
> >>Of course that was the first thing I tried, and it didn't help *at*
> >>*all*:
> >>
> >The -dusage=<number> is a means to an end, so if that doesn't work try
> >a larger number, up to 100.  Really once you pass 50 and it's not
> >working then it's time to just do a balance.  The next thing is to use
> >compression (too late for this option really) or add another disk.
> 
> So it relocates some chunks. What will that do? Does it mean I can
> now use the remaining 45 GB? Or will it run out of "disk space"
> again after using a gig or two?

   What it's done is moved some of the data around. One effect of this
process is that when a balance operation balances a chunk, it
deallocates that space. Therefore you should now see that the "used"
value for the device in btrfs fi show is lower than the "total" value.
Also, the "total" value for data in btrfs fi df should now be lower
than it was before.

   This means that the next time the FS needs some metadata space
(probably real soon now, because it was running out of it earlier), it
now has uncommitted space to allocate to metadata.

> If it's the allocated metadata space that is the problem then how
> can I pre-allocate more of it so it won't run out of it?

   It's possible that when filling up the remaining 45 GiB of space
the metadata will need to expand again, and you will need to run a
balance to do the same job again. Unless you have lots and lots of
small files or small fragments (or lots more snapshots than you've
been making to date), I'd say it's probably unlikely, though.

   Hugo.

-- 
=== Hugo Mills: hugo@... carfax.org.uk | darksatanic.net | lug.org.uk ===
  PGP key: 65E74AC0 from wwwkeys.eu.pgp.net or http://www.carfax.org.uk
        --- Well, sir, the floor is yours.  But remember, the ---        
                              roof is ours!                              

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