Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id E14BE411 for ; Sun, 29 Nov 2015 05:15:33 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from mail-pa0-f47.google.com (mail-pa0-f47.google.com [209.85.220.47]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 8F729172 for ; Sun, 29 Nov 2015 05:15:33 +0000 (UTC) Received: by pacej9 with SMTP id ej9so150271789pac.2 for ; Sat, 28 Nov 2015 21:15:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=subject:references:to:from:message-id:date:user-agent:mime-version :in-reply-to:content-type; bh=+MtC8rSDQH5vKBPnsHDsDZ+5FGqEaw6UXqN+8UpELYQ=; b=wmVBSblDurG/DEJ6M2P/YgS+T0VxFgS24GO/T3xlA3LQBYtmvTzv0KXGRqkOHf2HMN rjMncxlz7FWigguJ3M5cpTRdkwjtr5RYY+lsTYEgM7Yskz9Y6hkgw3EcvJVRFlZJXE0F jWf+VIo9IjXm2EathgNHDHQrlnyZJScPbMS2Ze1kfW/NAw3I7GNnvl3knQDJ3kAJyZux kuNoyR4ctvsq2ofzwppat/z5iHle1MKtwuXTEy9smB+NWv8qoTbwoA65xrX0oBwNTjfg JGHr6T5IqCNjZP/WW2CLMHETyuI3A3BH3QAv23FmuKZs0zsaBylpXXa8aKNCLpcJ3zhf IxbA== X-Received: by 10.66.139.131 with SMTP id qy3mr71847520pab.71.1448774133302; Sat, 28 Nov 2015 21:15:33 -0800 (PST) Received: from [192.168.0.132] (S0106bcd165303d84.cc.shawcable.net. [96.54.102.88]) by smtp.googlemail.com with ESMTPSA id r20sm42983893pfa.93.2015.11.28.21.15.32 for (version=TLSv1/SSLv3 cipher=OTHER); Sat, 28 Nov 2015 21:15:32 -0800 (PST) References: <5640F172.3010004@gmail.com> <20151109210449.GE5886@mcelrath.org> <5642172C.701@gmail.com> <5659BEC9.50307@gmail.com> <725E6BCC-E839-4F91-9BCA-95D0549DC3C7@toom.im> To: Bitcoin Dev From: Peter Tschipper Message-ID: <565A89F4.6070706@gmail.com> Date: Sat, 28 Nov 2015 21:15:32 -0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 MIME-Version: 1.0 In-Reply-To: <725E6BCC-E839-4F91-9BCA-95D0549DC3C7@toom.im> Content-Type: multipart/alternative; boundary="------------020806090405030202080405" X-Spam-Status: No, score=-2.7 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,HTML_MESSAGE,RCVD_IN_DNSWL_LOW autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org Subject: Re: [bitcoin-dev] further test results for : "Datastream Compression of Blocks and Tx's" X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Development Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 29 Nov 2015 05:15:34 -0000 This is a multi-part message in MIME format. --------------020806090405030202080405 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit yes, you're right, it's just the percentage compressed (size reduction) On 28/11/2015 4:30 PM, Jonathan Toomim wrote: > It appears you're using the term "compression ratio" to mean "size > reduction". A compression ratio is the ratio (compressed / > uncompressed). A 1 kB file compressed with a 10% compression ratio > would be 0.1 kB. It seems you're using (1 - compressed/uncompressed), > meaning that the compressed file would be 0.9 kB. > > On Nov 28, 2015, at 6:48 AM, Peter Tschipper via bitcoin-dev > > wrote: > >> The following show the compression ratio acheived for various sizes >> of data. Zlib is the clear >> winner for compressibility, with LZOx-999 coming close but at a cost. >> >> range Zlib-1 cmp% >> Zlib-6 cmp% LZOx-1 cmp% LZOx-999 cmp% >> 0-250b 12.44 12.86 10.79 14.34 >> 250-500b 19.33 12.97 10.34 11.11 >> >> >> >> >> >> > --------------020806090405030202080405 Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: 8bit
yes, you're right, it's just the percentage compressed (size reduction)

On 28/11/2015 4:30 PM, Jonathan Toomim wrote:
It appears you're using the term "compression ratio" to mean "size reduction". A compression ratio is the ratio (compressed / uncompressed). A 1 kB file compressed with a 10% compression ratio would be 0.1 kB. It seems you're using (1 - compressed/uncompressed), meaning that the compressed file would be 0.9 kB.

On Nov 28, 2015, at 6:48 AM, Peter Tschipper via bitcoin-dev <bitcoin-dev@lists.linuxfoundation.org> wrote:

The following show the compression ratio acheived for various sizes of data.  Zlib is the clear
winner for compressibility, with LZOx-999 coming close but at a cost.

range Zlib-1 cmp%
 Zlib-6 cmp% LZOx-1 cmp% LZOx-999 cmp%
0-250b 12.44 12.86 10.79 14.34
250-500b  19.33 12.97 10.34 11.11







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