From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794604619; b=xX/BPv6DCDjtERx8Q6PJcCM9tM3E2gL/ynJLNu9sNqe2+5LojOB7m0GzN4Jw0adkHOKO RzdQXVtwD4w5oFujKMO7BgQZdxSD8mN9zltG82tFYFDyruFJ5qC/Ccpp1silRQwUvWlpm gbrdnRsRTXW0xplt4U8LwpPxUkKeyNC6/cTfdeX+XnGSpvvxiQdXXSBZDGYYu0qlel8Fs EbvhIUTUe8JTWP2xHJMd64uC8H81RQkO/yDiDKJtmwS3FJ6v+UnOTWtSFGGNXussNzVFl F3WbSPTOK+Z15Br5nbZxhZly/i3nhIOaeWYRZ/VOAm7PBkRnIwqAARjT3WcHzbX5A0A== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794604619; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=MKS45e/R8A8a/j8IaYrH+BW6yvMJ8wilPZ4yAmXdI8U=; b=2VRjz5YJN+VLCUvnVrYEr8zx7f23r9E7XlnyWYFSPSb9Yy7jbAcOEu8uUpekp0muGC07 E6WDLLAt26K51lOrI1kGsYrx0lGdgUezvsoEMT0BONr/EFRzTqV6f69yBladN71N8AdL+ mSTUNt6ZlMOp7VMtyaBUnNWKvDXXcXi7YI/M++xyIkNvYJuw1I0yXMdFLhDLBueBCdx8R 0aAlTSYE1AtdddHcfq+ZYbZU5NQ7OP8I1aKLcNWGQkSi0jXogJtlYZJtWZH/G18tdvzsO j0+6dAlyes8Aiv7baseJ/npFYfbRxeK0XBOxu8lBHgQ9E0oBuSReDAZtb0xvztNO89A== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Qny4n2fD; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 775BC606A333 for ; Fri, 13 Nov 2026 21:16:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Qny4n2fD Received: by smtp.kernel.org (Postfix) with ESMTPSA id ED0631F000C4; Fri, 13 Nov 2026 21:16:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794604619; bh=MKS45e/R8A8a/j8IaYrH+BW6yvMJ8wilPZ4yAmXdI8U=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=Qny4n2fDS2boH8W2GXIYajAe/w6sRIe/Mo49pzZiUNU2h1GJFpvOkReQMCA3df9Fx jQE6lCJlG6rhmaV9bdRO5jkplBBk7V/6vitlXqdKZu0VcEDrw1JehODRpu5KNXfEI4 8vXxw8EdLT5hS/sbZeoqcpl6LDbMWi+/f94WKz5wqNbGo6nafmUzOyvTGXsi3W0C17 3pgbD3Hw7bg+nCS71EhX48XEV7c/dC1yqBf2NK3unMbzhqApEp4ETVbaM7GzSuEjpU BMBxF7Pk8qu6Tov9D6uSflJO9G/fhBXyPdgZQXV2tGeSR6mIS7VwTS2nWxB0nc0x0j TxY1HEscU49Xw== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH 05/10] perf jevents: Add block-indexed string packing and --compress=zlib Reply-To: sashiko-reviews@lists.linux.dev To: "Ian Rogers" Cc: linux-perf-users@vger.kernel.org In-Reply-To: <20261113210822.3112700-6-irogers@google.com> References: <20261113210822.3112700-1-irogers@google.com> <20261113210822.3112700-6-irogers@google.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Fri, 13 Nov 2026 21:16:58 +0000 X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > Compressing big_c_string (~6.9 MiB on x86) as a single monolithic stream > would force perf to allocate and decompress megabytes of unused CPU > models' strings on startup just to look up a single event or metric, > whereas compressing each short string individually suffers from poor > compression ratios and per-string framing overhead. >=20 > Introduce "block-indexed string compression" via a --compress=3D > option to jevents.py (defaulting to 'none'): > - Sorted, non-folded BigCString byte records are packed sequentially > into ~8 KiB blocks without splitting any multi-field event or metric > record across a block boundary (with suffix-folded strings inheriting > their parent record's block and intra-block offset plus suffix delta). > - Each block is compressed independently into big_c_string_blob[], > indexed by big_c_string_block_offsets[] and big_c_string_raw_lens[], > while sharing a common dictionary across blocks so ~8 KiB blocks > [ ... ] > --compress=3Dzlib shrinks pmu-events-string.o from ~6.90 MB to ~716 KB > (~9.6x reduction) while only decompressing touched 8 KiB blocks on > demand. >=20 > Signed-off-by: Ian Rogers Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261113210822.3112= 700-1-irogers@google.com?part=3D5