> When tuning recordsize for things like databases, we
> try to recommend
> that the customer's recordsize match the I/O size of
> the database
> record.
On this filesystem I have:
- file links and they are rather static
- small files ( about 8kB ) that keeps changing
- big files ( 1MB - 20 MB
> But now I have another question.
> How 8k blocks will impact on performance ?
When tuning recordsize for things like databases, we try to recommend
that the customer's recordsize match the I/O size of the database
record.
I don't think that's the case in your situation. ZFS is clever enough
th
Łukasz пишет:
> After few hours with dtrace and source code browsing I found that in my space
> map there are no 128K blocks left.
Actually you may have some 128k or more free space segments, but
alignment requirements will not allow to allocate them. Consider the
following example:
1. Space
If you want to know which blocks you do not have:
dtrace -n fbt::metaslab_group_alloc:entry'{ self->s = arg1; }' -n
fbt::metaslab_group_alloc:return'/arg1 != -1/{ self->s = 0 }' -n
fbt::metaslab_group_alloc:return'/self->s && (arg1 == -1)/{ @s =
quantize(self->s); self->s = 0; }' -n tick-10s'{
After few hours with dtrace and source code browsing I found that in my space
map there are no 128K blocks left.
Try this on your ZFS.
dtrace -n fbt::metaslab_group_alloc:return'/arg1 == -1/{}
If you will get probes, then you also have the same problem.
Allocating from space map works like th
Field ms_smo.smo_objsize in metaslab struct is size of data on disk.
I checked the size of metaslabs in memory:
::walk spa | ::walk metaslab | ::print struct metaslab
ms_map.sm_root.avl_numnodes
I got 1GB
But only some metaslabs are loaded:
::walk spa | ::walk metaslab | ::print struct metaslab
This system exhibits the symptoms of :
http://bugs.opensolaris.org/bugdatabase/view_bug.do?bug_id=6495013
Moving to nevada would certainly help as it has many more bug fixes and
performance improvements over S10U3.
--
Prabahar.
?ukasz wrote:
> Hello,
> I'm investigating problem with ZFS ove
