Really, as i lay in the bath thinking nabout it, I concluded what I am
looking for is a very limited form of Consistency.
Its consistency over a single row on a single node just for the period of
update.
On Thu, Jul 7, 2011 at 10:34 PM, Jeffrey Kesselman wrote:
> Its not really isolation, btw,
Does CASSANDRA-809 resolved or any other path can resolve the problem? Is there
any way to avoid reboot the cassandra server?
Thanks!
Best Regards
Donna li
-邮件原件-
发件人: Jonathan Ellis [mailto:jbel...@gmail.com]
发送时间: 2011年7月8日 11:03
收件人: user@cassandra.apache.org
主题: Re: cassandra serve
Yeah, ideally it should probably die or drop into read-only mode if it
runs out of space.
(https://issues.apache.org/jira/browse/CASSANDRA-809)
Unfortunately dealing with disk-full conditions tends to be a low
priority for many people because it's relatively easy to avoid with
decent monitoring, b
Its not really isolation, btw, because we arent talking about anyone seeing
an update mid-update.Rather, we are talking about when updates are
allowed to occur.
Atomicity means that all the updates happen together or they don't happen at
all.
Isolation means that no results of the update are v
Not confusing, but assuming a few things.
I made a more detailed post in the Datatstax forums.
On Thu, Jul 7, 2011 at 10:27 PM, Jonathan Ellis wrote:
> Sounds to me like you're confusing atomicity with isolation.
>
> On Thu, Jul 7, 2011 at 2:54 PM, Jeffrey Kesselman
> wrote:
> > Yup, im even m
Sounds to me like you're confusing atomicity with isolation.
On Thu, Jul 7, 2011 at 2:54 PM, Jeffrey Kesselman wrote:
> Yup, im even more confused. Lets talk about the model, not the
> implementation.
> AIUI updates to a row are atomic across all columns in that row at once,
> true?
> If true
All:
When one of the cassandra servers disk full, the cluster can not work
normally, even I make space. I must reboot the server that disk full,
the cluster can work normally.
Best Regards
Donna li
Does a 'select * from ' with no filter still use the primary
index on the key or do a 'full table scan' ?
Thanks.
Yup, im even more confused.Lets tlak about the model, not the
implementation.
AIUI updates to a single row are atomic across all columns in that row at
once, true?
If true then the next question is, does the validation happen inside or
outside of that guarantee, and is the row guaranteed not
Yup, im even more confused.Lets talk about the model, not the
implementation.
AIUI updates to a row are atomic across all columns in that row at once,
true?
If true then the next question is, does the validation happen inside or
outside of that guarantee, and is the row guaranteed not to chan
no , the memtable is a concurrentskiplistmap
insertion can happen in parallel
On Jul 7, 2011 9:24 AM, "Jeffrey Kesselman" wrote:
> This has me more confused.
>
> Does this mean that ALL rows on a given node are only updated
sequentially,
> never in parallel?
>
> On Thu, Jul 7, 2011 at 3:21 PM, Ya
The old row is accessible and my validation requires a comparison of the
two.
JK
On Thu, Jul 7, 2011 at 3:23 PM, Yang wrote:
> validation is on the new incoming column ,not the old row,right?
> On Jul 7, 2011 8:25 AM, "Jeffrey Kesselman" wrote:
> > Hi Jonnathan,
> >
> > This brings up an impo
This has me more confused.
Does this mean that ALL rows on a given node are only updated sequentially,
never in parallel?
On Thu, Jul 7, 2011 at 3:21 PM, Yang wrote:
> just to add onto what jonathan said
>
> the columns are immutable . if u overwrite/ reconcile a new obj is
> created and
validation is on the new incoming column ,not the old row,right?
On Jul 7, 2011 8:25 AM, "Jeffrey Kesselman" wrote:
> Hi Jonnathan,
>
> This brings up an important question. I have been assuming that the
> validation check is part of the atomic update operation. Is this NOT the
> case? Which is t
just to add onto what jonathan said
the columns are immutable . if u overwrite/ reconcile a new obj is
created and shoved into the memtable
there is a shared lock for all writes though which guard against an
exclusive lock on memtable switching/flushing
On Jul 7, 2011 7:51 AM, "A J" wrote:
Hi Jonnathan,
This brings up an important question. I have been assuming that the
validation check is part of the atomic update operation. Is this NOT the
case? Which is to say, can the row be changed between the time the
validation method is executed and the validated data is written?
The reas
None of the above, it uses a glorified CAS* at the column level
*http://en.wikipedia.org/wiki/Compare-and-swap
On Thu, Jul 7, 2011 at 12:51 PM, A J wrote:
> Does a write lock:
> 1. Just the columns in question for the specific row in question ?
> 2. The full row in question ?
> 3. The full CF ?
Does a write lock:
1. Just the columns in question for the specific row in question ?
2. The full row in question ?
3. The full CF ?
I doubt read does any locks.
Thanks.
May I ask if its opensource by any chance ?
bye
norman
Am Donnerstag, 7. Juli 2011 schrieb David Strauss :
> I'm not sure HDFS has the right properties for a media-storage file
> system. We have, however, built a WebDAV server on top of Cassandra
> that avoids any pretension of being a general-pu
Is there a way to find what all nodes was a write applied to ? It
could be a successful write (i.e. w was met) or unsuccessful write
(i.e. less than w nodes were met). In either case, I am interested in
finding:
Number of nodes written to (before timeout or on success)
Name of nodes written to (bef
I'm not sure HDFS has the right properties for a media-storage file
system. We have, however, built a WebDAV server on top of Cassandra
that avoids any pretension of being a general-purpose, POSIX-compliant
file system. We mount it on our servers using davfs2, which is also
nice for a few reasons:
On Thu, Jul 7, 2011 at 3:39 PM, A J wrote:
> Thanks. The above works.
> But when I try to use the binary values rather than the hex values, it
> does not work. i.e. instead of using 64ff, I use 01100100. Instead of
> 6Dff, I use 01101101.
> When using the binary values, everything (strings startin
On Thu, Jul 7, 2011 at 11:14 AM, Eric tamme wrote:
> On Thu, Jul 7, 2011 at 11:09 AM, A J wrote:
> > https://www.packtpub.com/cassandra-apache-high-performance-cookbook/book
> >
>
> I think last Ed said was "soon" ha ha. The book is done, and I think
> it's up to the publisher at this point. M
Hello Torsten,
I am working on Cassandra for last 4 weeks and am trying to
load large amount of data.Data is in a csv file.I am trying to use the Bulk
loading technique but am not clear with the process.Could you please explain
the process for the bulk load?
Thanks,
Priyanka
-
On Thu, Jul 7, 2011 at 11:09 AM, A J wrote:
> https://www.packtpub.com/cassandra-apache-high-performance-cookbook/book
>
I think last Ed said was "soon" ha ha. The book is done, and I think
it's up to the publisher at this point. Maybe a couple of weeks? Ed?
https://www.packtpub.com/cassandra-apache-high-performance-cookbook/book
Thanks. The above works.
But when I try to use the binary values rather than the hex values, it
does not work. i.e. instead of using 64ff, I use 01100100. Instead of
6Dff, I use 01101101.
When using the binary values, everything (strings starting with a to
z) seem to be going to n1 only.
Any idea w
We are running into the same issue on some of our machines. Still
haven't tracked down what is causing it.
From: William Oberman [mailto:ober...@civicscience.com]
Sent: Thursday, July 07, 2011 7:19 AM
To: user@cassandra.apache.org
Subject: Re: Cassandra memory p
I think I had (and have) a similar problem:
http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/OOM-or-what-settings-to-use-on-AWS-large-td6504060.html
My memory usage grew slowly until I ran out of mem and the OS killed my
process (due to no swap).
I'm still on 0.7.4, but I'm rolling
Hm - had to digg deeper and it totally looks like a native mem leak to me:
We are still growing with res += 100MB a day. Cassandra is > 8G now
I checked the cassandra process with pmap -x
Here's the human readable (aggregated) output:
Format is thingy: RSS in KB
Summary:
Total SST: 1961616
An
> is this behaviour expected since the RF (for the duration of when 1 node was
> taken out)
> is higher than the # of nodes?
Note that repair is not needed just because a node was off for a while.
I am guessing the performance difference was due to the repair. Try
running repair at any time and s
cheers~
On 7 July 2011 19:41, Watanabe Maki wrote:
> It is expected behaviour and not relate on number of node.
> After the failed node bringing back, the ring will be busy by Hinted
> Handoff rewriting and Read Repair. If you run repair, all your 3 nodes need
> to build Merkel Tree, compare the
It is expected behaviour and not relate on number of node.
After the failed node bringing back, the ring will be busy by Hinted Handoff
rewriting and Read Repair. If you run repair, all your 3 nodes need to build
Merkel Tree, compare the hash values, then transfer latest data to each other.
You
hi guys,
is there a minimum(recommended) number of machines for RF=3?
i encountered a test result where
# of nodes = 3
RF = 3
CL.READ=QUORUM
and when 1 node was taken out and back in after which node repair was run,
the TPS dropped significantly.
is this behaviour expected since the RF (for th
Thanks,
Is it possible to have same results sorting in reversed by another method
without get_range_slice in JAVA ?
De : Aaron Morton
À : "user@cassandra.apache.org"
Envoyé le : Jeudi 7 Juillet 2011 2h52
Objet : Re: result sorted by keys in reversed
It's no
You can use Watchitoo.com (LIke GoToMeeting/WebEX) to host an event.
using that tool, everyone around the world can join and take action.
the great thing about is that it's FREE!
On Wed, Jul 6, 2011 at 10:25 PM, Mike Rapuano wrote:
> Hi all
>
> Are there any active cassandra meet ups in souther
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