From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Wed, 6 Feb 2019 13:46:28 +0300 From: Konstantin Osipov Subject: Re: [tarantool-patches] Re: [PATCH 3/9] vinyl: use uncompressed run size for range split/coalesce/compaction Message-ID: <20190206104628.GE19953@chai> References: <20190121094213.yzfawcs7mgkqxi3e@esperanza> <20190205164905.GC6811@chai> <20190206085506.aoj3chculmmqoexr@esperanza> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190206085506.aoj3chculmmqoexr@esperanza> To: Vladimir Davydov Cc: tarantool-patches@freelists.org List-ID: * Vladimir Davydov [19/02/06 13:31]: > Only because after the patch I don't need to use random() to generate > data that would trigger compaction - compaction logic uses uncompressed > sizes now so we can use string.rep(), which is faster. It is faster but it may impact other properties of the runs - like physical run size. For example you begin getting much more pages per run, for all runs except the top-level one. I would avoid using string.rep() anywhere in vinyl test data, unless I intentionally want to check the effects of inserting data with high compression rate. -- Konstantin Osipov, Moscow, Russia, +7 903 626 22 32 http://tarantool.io - www.twitter.com/kostja_osipov