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From: Jens Axboe <axboe@kernel.dk>
To: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Recent slowdown in single object builds
Date: Fri, 15 Nov 2019 16:10:42 -0700	[thread overview]
Message-ID: <d60946a1-fde3-ee6f-683a-42a611768bbf@kernel.dk> (raw)

Hi,

I've noticed that current -git is a lot slower at doing single object
builds than earlier kernels. Here's an example, building the exact same
file on 5.2 and -git:

$ time make fs/io_uring.o
real    0m5.953s
user    0m5.402s
sys     0m0.649s

vs 5.2 based (with all the backports, identical file):

$ time make fs/io_uring.o
real    0m3.218s
user    0m2.968s
sys     0m0.520s

Any idea what's going on here? It's almost twice as slow, which is
problematic...

-- 
Jens Axboe


             reply	other threads:[~2019-11-15 23:10 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-15 23:10 Jens Axboe [this message]
2019-11-16  7:17 ` Masahiro Yamada
2019-11-16 16:57   ` Jens Axboe
2019-11-18  0:40     ` Masahiro Yamada
2019-11-18  2:34       ` Jens Axboe

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