From user-return-24479-apmail-cassandra-user-archive=cassandra.apache.org@cassandra.apache.org Thu Mar 1 10:13:46 2012 Return-Path: X-Original-To: apmail-cassandra-user-archive@www.apache.org Delivered-To: apmail-cassandra-user-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 832769894 for ; Thu, 1 Mar 2012 10:13:46 +0000 (UTC) Received: (qmail 81400 invoked by uid 500); 1 Mar 2012 10:13:44 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 81366 invoked by uid 500); 1 Mar 2012 10:13:43 -0000 Mailing-List: contact user-help@cassandra.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@cassandra.apache.org Delivered-To: mailing list user@cassandra.apache.org Received: (qmail 81358 invoked by uid 99); 1 Mar 2012 10:13:43 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 01 Mar 2012 10:13:43 +0000 X-ASF-Spam-Status: No, hits=2.2 required=5.0 tests=HTML_MESSAGE,RCVD_IN_DNSWL_NONE,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: local policy) Received: from [208.113.200.5] (HELO homiemail-a42.g.dreamhost.com) (208.113.200.5) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 01 Mar 2012 10:13:36 +0000 Received: from homiemail-a42.g.dreamhost.com (localhost [127.0.0.1]) by homiemail-a42.g.dreamhost.com (Postfix) with ESMTP id 1A10668C05D for ; Thu, 1 Mar 2012 02:13:15 -0800 (PST) DomainKey-Signature: a=rsa-sha1; c=nofws; d=thelastpickle.com; h=from :mime-version:content-type:subject:date:in-reply-to:to :references:message-id; q=dns; s=thelastpickle.com; b=v9U8NY5Wlf FXfUasIXIXc10UVYOyYeZppYfIXNYI65irlVHINUI4L1gAeVWN8cIVuxNIfEMd5y NQE3cu3+Bi3vlUG/9RMCKBOkWAjuadQ59P82pESqaMaDfVj8+aZ/5vVo+9NQbjH/ KWmbqy3VNPEby1F43Gd7d12+CjeIVcy3g= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=thelastpickle.com; h=from :mime-version:content-type:subject:date:in-reply-to:to :references:message-id; s=thelastpickle.com; bh=MCOyYjTzuBnRj2Ge AvtS1W2XeEI=; b=yA5Cz5IWDHVzjIUXj5BYJNPJzy64VLtjWLYrdlFKSx01TR9d MgPnbAfEgKbb54cRXP9L6i0wfdj2KFyrIn+3w63ynbT0m0gVeIrx++ZimTyOXhv2 jMPdVpsNdBNrJTHjmgj2aVDkwDTYWIcd/8Iszz7lRYWie336GsDrC9gXe6M= Received: from [172.16.1.3] (125-236-193-159.adsl.xtra.co.nz [125.236.193.159]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) (Authenticated sender: aaron@thelastpickle.com) by homiemail-a42.g.dreamhost.com (Postfix) with ESMTPSA id 7FA7D68C05F for ; Thu, 1 Mar 2012 02:13:14 -0800 (PST) From: aaron morton Mime-Version: 1.0 (Apple Message framework v1257) Content-Type: multipart/alternative; boundary="Apple-Mail=_506A7A42-47DE-45E9-A771-B1D1AE6F379B" Subject: Re: Using cassandra at minimal expenditures Date: Thu, 1 Mar 2012 23:13:10 +1300 In-Reply-To: To: user@cassandra.apache.org References: <4824CA7B-7D94-4F66-B181-E33992A4ED3B@thelastpickle.com> Message-Id: <0860D218-3D06-4B81-A987-3468A1DCC36D@thelastpickle.com> X-Mailer: Apple Mail (2.1257) X-Virus-Checked: Checked by ClamAV on apache.org --Apple-Mail=_506A7A42-47DE-45E9-A771-B1D1AE6F379B Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=iso-8859-1 As others said, depends on load and traffic and all sorts of thins.=20 if you want a number, 4Gb would me a reasonable minimum IMHO. (You may = get by with less). 8Gb is about the tops.=20 Any memory not allocated to Cassandra will be used to map files into = memory.=20 If you can get machines with 8GB ram thats a reasonable start. ----------------- Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 1/03/2012, at 1:16 AM, Maki Watanabe wrote: > Depends on your traffic :-) >=20 > cassandra-env.sh will try to allocate heap with following formula if > you don't specify MAX_HEAP_SIZE. > 1. calculate 1/2 of RAM on your system and cap to 1024MB > 2. calculate 1/4 of RAM on your system and cap to 8192MB > 3. pick the larger value >=20 > So how about to start with the default? You will need to monitor the > heap usage at first. >=20 > 2012/2/29 Ertio Lew : >> Thanks, I think I don't need high consistency(as per my app = requirements) so >> I might be fine with CL.ONE instead of quorum, so I think I'm = probably >> going to be ok with a 2 node cluster initially.. >>=20 >> Could you guys also recommend some minimum memory to start with ? Of = course >> that would depend on my workload as well, but that's why I am asking = for the >> min >>=20 >>=20 >> On Wed, Feb 29, 2012 at 7:40 AM, Maki Watanabe = >> wrote: >>>=20 >>>> If you run your service with 2 node and RF=3D2, your data will be >>>> replicated but >>>> your service will not be redundant. ( You can't stop both of nodes = ) >>>=20 >>> If your service doesn't need strong consistency ( allow cassandra = returns >>> "old" data after write, and possible write lost ), you can use = CL=3DONE >>> for read and write >>> to keep availability. >>>=20 >>> maki >>=20 >>=20 >=20 >=20 >=20 > --=20 > w3m --Apple-Mail=_506A7A42-47DE-45E9-A771-B1D1AE6F379B Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=iso-8859-1 As = others said, depends on load and traffic and all sorts of = thins. 

if you want a number, 4Gb would me a = reasonable minimum IMHO. (You may get by with less).  8Gb is about = the tops. 
Any memory not allocated to Cassandra =  will be used to map files into = memory. 

If you can get machines with 8GB = ram thats a reasonable start.

http://www.thelastpickle.com

On 1/03/2012, at 1:16 AM, Maki Watanabe wrote:

Depends= on your traffic :-)

cassandra-env.sh will try to allocate heap = with following formula if
you don't specify MAX_HEAP_SIZE.
1. = calculate 1/2 of RAM on your system and cap to 1024MB
2. calculate = 1/4 of RAM on your system and cap to 8192MB
3. pick the larger = value

So how about to start with the default? You will need to = monitor the
heap usage at first.

2012/2/29 Ertio Lew <ertiop93@gmail.com>:
Thanks, I think I don't need high consistency(as per = my app requirements) so
I = might be fine with CL.ONE instead of quorum, so I think  = I'm probably
going to be = ok with a 2 node cluster initially..

Could you guys = also recommend some minimum memory to start with ? Of = course
that would depend on my = workload as well, but that's why I am asking for = the
min


On Wed, Feb 29, = 2012 at 7:40 AM, Maki Watanabe <watanabe.maki@gmail.com>
wrote:

If you = run your service with 2 node and RF=3D2, your data will = be
replicated = but
your = service will not be redundant. ( You can't stop both of nodes = )

If your service doesn't need = strong consistency ( allow cassandra = returns
"old" data after write, and possible write lost ), you = can use CL=3DONE
for read and = write
to keep = availability.

maki





-- =
w3m

= --Apple-Mail=_506A7A42-47DE-45E9-A771-B1D1AE6F379B--