On 20.04.2016 12:10, Andreas Joseph
Krogh wrote:
On 20.04.2016 11:40, Andreas Joseph
Krogh wrote:
On 20.04.2016 11:29, Devrim Gündüz wrote:
> Hi,
>
> On Wed, 2016-04-20 at 10:43 +0300, Alex Ignatov
wrote:
>> Today in Big Data epoch silent data corruption
becoming more and more
>> issue to afraid of. With uncorrectable read error
rate ~ 10^-15 on
>> multiterabyte disk bit rot is the real issue.
>> I think that today checksumming data must be
mandatory set by default.
>> Only if someone doesn't care about his data he
can manually turn this
>> option off.
>>
>> What do you think about defaulting
--data-checksums in initdb?
> I think this should be discussed in -hackers, right?
>
> Regards,
May be you right but i want to know what people think
about it before
i'll write to hackers.
-1 on changing the default.
10^15 ~= 1000 TB, which isn't very common yet. Those
having it probably are aware of the risk and have enabled
checksums already.
--
Andreas
Joseph Krogh
CTO
/ Partner - Visena AS
Mobile:
+47 909 56 963
It is per bit not bytes. So it is ~100 TB. We working with some
enterprise who have WALs creation rate ~ 4GB per min - so it is
only max 100 days before you get bit rotted and have probability
to get silent data corruption.
Also don't forget that it is theoretical limit and Google tells
us that HDD and SSD is not as reliable as manufactures tell. So
this 10^-15 can easily be much higher.
Ok, but still - the case you're describing isn't the
common-case for PG-users. Enterprises like that certainly chould
use --data-checksums, I'm not arguing against that, just that it
shouldn't be the default-setting.
--
Andreas
Joseph Krogh
CTO
/ Partner - Visena AS
Mobile:
+47 909 56 963
Why do you think that common pg-users doesn't care about their data?
Also why do we have wal_level=minimal fsync=on and other stuff?
--
Alex Ignatov
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company
|
