On Wed, Jul 6, 2011 at 6:17 AM, John R Pierce <pierce@xxxxxxxxxxxx> wrote:
> On 07/05/11 9:04 PM, Charles Polisher wrote:
>> The PostgreSQL wiki seems to say that database tables are
>> allocated in 1GB extents. In workloads with which I am
>> familiar, with an RDBMS the extents don't bounce
>> around all that much, i.e. the vast majority of writes do
>> not result in a change to the underlying database's storage
>> allocation. Once in a while a new extent is allocated.
>> http://www.postgresql.org/docs/current/static/storage-file-layout.html
>> I suppose there could be exceptions, but I haven't run
>> across one personally.
>
> you misread that.
>
> When a table or index exceeds 1 GB, it is divided into
> gigabyte-sized/segments/. The first segment's file name is the same
> as the filenode; subsequent segments are named filenode.1,
> filenode.2, etc. This arrangement avoids problems on platforms that
> have file size limitations. ...
>
>
> Each file is no larger than 1GB (by default), but its written and
> expanded as needed, not in any fixed size increment.
>
>
>> The "WAL" files you refer to are apparently database
>> transaction logs. According to the wiki, these too
>> are allocated in extents (WAL segments) of 16MB each.
>
> The wal logs are 16M files, also written sequentially as needed, and
> nearly continuously on a insert/update intensive database. they are not
> reused, rather, old wal files are deleted (unless you're archiving), and
> new ones are created continuously.
>
>
> --
> john r pierce N 37, W 122
> santa cruz ca mid-left coast
>
> _______________________________________________
Hi Everyone,
I just tried to install EXT4 onto a CentOS 5 machine but it failed.
Does anyone know in which repository it is?
root@usaxen01:[~]$ cat /etc/redhat-release
CentOS release 5 (Final)
root@usaxen01:[~]$ uname -a
Linux usaxen01 2.6.18-8.1.15.el5xen #1 SMP Mon Oct 22 09:01:12 EDT
2007 x86_64 x86_64 x86_64 GNU/Linux
root@usaxen01:[~]$ yum -y install e4fsprogs
Loading "installonlyn" plugin
Setting up Install Process
Setting up repositories
Reading repository metadata in from local files
Excluding Packages in global exclude list
Finished
Parsing package install arguments
Nothing to do
--
Kind Regards
Rudi Ahlers
SoftDux
Website: http://www.SoftDux.com
Technical Blog: http://Blog.SoftDux.com
Office: 087 805 9573
Cell: 082 554 7532
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