From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6F7CEC43381 for ; Tue, 5 Mar 2019 12:25:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3FA192082C for ; Tue, 5 Mar 2019 12:25:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728189AbfCEMZz (ORCPT ); Tue, 5 Mar 2019 07:25:55 -0500 Received: from mx1.redhat.com ([209.132.183.28]:49066 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728027AbfCEMZz (ORCPT ); Tue, 5 Mar 2019 07:25:55 -0500 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D105010C6D; Tue, 5 Mar 2019 12:25:54 +0000 (UTC) Received: from krava (unknown [10.43.17.112]) by smtp.corp.redhat.com (Postfix) with SMTP id 2870E1001DC5; Tue, 5 Mar 2019 12:25:52 +0000 (UTC) Date: Tue, 5 Mar 2019 13:25:52 +0100 From: Jiri Olsa To: Alexey Budankov Cc: Arnaldo Carvalho de Melo , Namhyung Kim , Alexander Shishkin , Peter Zijlstra , Ingo Molnar , Andi Kleen , linux-kernel Subject: Re: [PATCH v5 07/10] perf record: implement -z,--compression_level=n option and compression Message-ID: <20190305122552.GE16615@krava> References: <4d1b11a4-77ed-d9af-ed22-875fc17b6050@linux.intel.com> <87fa1906-2d6a-a00a-7ba5-b570d0cbf9cc@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87fa1906-2d6a-a00a-7ba5-b570d0cbf9cc@linux.intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Tue, 05 Mar 2019 12:25:54 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 01, 2019 at 06:58:32PM +0300, Alexey Budankov wrote: SNIP > +static size_t record__zstd_compress(void *data, void *dst, size_t dst_size, > + void *src, size_t src_size) > +{ > + size_t compressed; > + struct perf_session *session = data; > + /* maximum size of record data size (2^16 - 1 - header) */ > + const size_t max_record_size = (1 << 8 * sizeof(u16)) - I dont follow this calculation, could you just use PERF_SAMPLE_MAX_SIZE? jirka > + 1 - sizeof(struct compressed_event); > + SNIP