From: Kent Overstreet <kent.overstreet@gmail.com>
To: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org,
pmladek@suse.com, rostedt@goodmis.org, enozhatsky@chromium.org,
willy@infradead.org
Subject: Re: [PATCH v4 00/34] Printbufs - new data structure for building strings
Date: Tue, 21 Jun 2022 04:01:20 -0400 [thread overview]
Message-ID: <20220621080120.bzms2aswvjld6nnp@moria.home.lan> (raw)
In-Reply-To: <46fcdf08-4646-afa0-c112-76d9335adb6c@rasmusvillemoes.dk>
On Tue, Jun 21, 2022 at 08:11:49AM +0200, Rasmus Villemoes wrote:
> On 20/06/2022 02.41, Kent Overstreet wrote:
>
> > Rasmus pointed out that -fno-strict-aliasing is going to cause gcc to generate
> > nasty code, and indeed it unfortunately does but according to worst case
> > scenario microbenchmarks it's not a problem for actual performance.
>
> Well, that's not how I interpreted those numbers, but, except if they
> showed an improvement, how much is acceptable is of course always a
> matter of judgment.
>
> However, what's really annoying and somewhat dishonest is that you're
> not including those numbers, nor the methodology, in either the cover
> letter or commit itself.
There's nothing dishonest about it, and I wasn't claiming an improvement; merely
no regressions (some were a 5-10% percent up, some down by around the same
amount, overall it was a wash).
My priority simply isn't microoptimizing everything. I find that programmers who
chase optimizing every loop and are constantly trying to shave instructions
everywhere they can end up with code where the large scale structure is a mess,
and that's where you miss out on the _real_ performance opportunities.
My priority is clean, readable, simple, easy to work on code, because _that_ is
the code that becomes fast in the long run.
Premature optimization really is the root of all evil, and I am _absolutely_
going to try to drive the discussion away from shaving cycles when there's new
APIs to get right and messy refactorings to complete.
next prev parent reply other threads:[~2022-06-21 8:01 UTC|newest]
Thread overview: 85+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-20 0:41 [PATCH v4 00/34] Printbufs - new data structure for building strings Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 01/34] lib/printbuf: New data structure for printing strings Kent Overstreet
2022-06-20 4:44 ` David Laight
2022-06-20 15:30 ` Kent Overstreet
2022-06-20 15:53 ` David Laight
2022-06-20 16:14 ` Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 02/34] lib/string_helpers: Convert string_escape_mem() to printbuf Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 03/34] vsprintf: Convert " Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 04/34] lib/hexdump: " Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 05/34] vsprintf: %pf(%p) Kent Overstreet
2022-06-21 7:04 ` Rasmus Villemoes
2022-06-21 7:51 ` Kent Overstreet
2022-06-21 8:47 ` Rasmus Villemoes
2022-06-21 11:11 ` David Laight
2022-06-20 0:42 ` [PATCH v4 06/34] lib/string_helpers: string_get_size() now returns characters wrote Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 07/34] lib/printbuf: Heap allocation Kent Overstreet
2022-06-21 7:58 ` Rasmus Villemoes
2022-06-20 0:42 ` [PATCH v4 08/34] lib/printbuf: Tabstops, indenting Kent Overstreet
2022-06-21 8:14 ` Rasmus Villemoes
2022-06-20 0:42 ` [PATCH v4 09/34] lib/printbuf: Unit specifiers Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 10/34] lib/pretty-printers: prt_string_option(), prt_bitflags() Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 11/34] vsprintf: Improve number() Kent Overstreet
2022-06-21 8:33 ` Rasmus Villemoes
2022-06-20 0:42 ` [PATCH v4 12/34] vsprintf: prt_u64_minwidth(), prt_u64() Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 13/34] test_printf: Drop requirement that sprintf not write past nul Kent Overstreet
2022-06-21 7:19 ` Rasmus Villemoes
2022-06-21 7:52 ` Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 14/34] vsprintf: Start consolidating printf_spec handling Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 15/34] vsprintf: Refactor resource_string() Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 16/34] vsprintf: Refactor fourcc_string() Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 17/34] vsprintf: Refactor ip_addr_string() Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 18/34] vsprintf: Refactor mac_address_string() Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 19/34] vsprintf: time_and_date() no longer takes printf_spec Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 20/34] vsprintf: flags_string() " Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 21/34] vsprintf: Refactor device_node_string, fwnode_string Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 22/34] vsprintf: Refactor hex_string, bitmap_string_list, bitmap_string Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 23/34] Input/joystick/analog: Convert from seq_buf -> printbuf Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 24/34] mm/memcontrol.c: Convert to printbuf Kent Overstreet
2022-06-20 11:37 ` Michal Hocko
2022-06-20 15:13 ` Kent Overstreet
2022-06-20 15:52 ` Michal Hocko
2022-06-20 0:42 ` [PATCH v4 25/34] clk: tegra: bpmp: " Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 26/34] tools/testing/nvdimm: " Kent Overstreet
2022-06-24 19:32 ` Dan Williams
2022-06-24 23:42 ` Santosh Sivaraj
2022-07-01 6:32 ` Shivaprasad G Bhat
2022-06-20 0:42 ` [PATCH v4 27/34] powerpc: " Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 28/34] x86/resctrl: " Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 29/34] PCI/P2PDMA: " Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 30/34] tracing: trace_events_synth: " Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 31/34] d_path: prt_path() Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 32/34] ACPI/APEI: Add missing include Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 33/34] tracing: Convert to printbuf Kent Overstreet
2022-06-20 0:42 ` [PATCH v4 34/34] Delete seq_buf Kent Overstreet
2022-06-20 4:19 ` [PATCH v4 00/34] Printbufs - new data structure for building strings David Laight
2022-06-20 4:54 ` Matthew Wilcox
2022-06-20 8:00 ` David Laight
2022-06-20 15:07 ` Kent Overstreet
2022-06-20 15:21 ` David Laight
2022-06-21 0:38 ` Joe Perches
2022-06-21 0:57 ` Kent Overstreet
2022-06-21 1:26 ` Joe Perches
2022-06-21 2:10 ` Joe Perches
2022-06-26 19:53 ` [RFC[ Alloc in vsprintf Joe Perches
2022-06-26 20:06 ` Kent Overstreet
2022-06-26 20:13 ` Joe Perches
2022-06-26 20:19 ` Linus Torvalds
2022-06-26 20:39 ` Joe Perches
2022-06-26 20:51 ` Kent Overstreet
2022-06-26 21:02 ` Joe Perches
2022-06-26 21:10 ` Kent Overstreet
2022-06-26 20:54 ` Linus Torvalds
2022-06-27 8:25 ` David Laight
2022-06-28 2:56 ` Kent Overstreet
2022-06-21 2:31 ` [PATCH v4 00/34] Printbufs - new data structure for building strings Kent Overstreet
2022-06-21 3:11 ` Kent Overstreet
2022-06-21 6:11 ` Rasmus Villemoes
2022-06-21 8:01 ` Kent Overstreet [this message]
2022-07-19 23:15 ` Steven Rostedt
2022-07-19 23:43 ` Kent Overstreet
2022-07-20 0:05 ` Steven Rostedt
2022-07-20 0:17 ` Kent Overstreet
2022-07-20 1:11 ` Steven Rostedt
2022-07-20 1:31 ` Kent Overstreet
2022-07-20 1:37 ` Steven Rostedt
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