From mboxrd@z Thu Jan  1 00:00:00 1970
From: Guan Junxiong <guanjunxiong@huawei.com>
Subject: Re: [PATCH 1/4] libmultipath: path latency: fix default
	base num
Date: Sun, 19 Nov 2017 10:19:57 +0800
Message-ID: <1f0d7fa6-df44-331d-e9ef-d50da51c5723@huawei.com>
References: <20171118001134.26622-1-mwilck@suse.com>
	<20171118001134.26622-2-mwilck@suse.com>
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To: Martin Wilck <mwilck@suse.com>, Christophe Varoqui <christophe.varoqui@opensvc.com>
Cc: dm-devel@redhat.com, niuhaoxin <niuhaoxin@huawei.com>, "Shenhong (C)" <shenhong09@huawei.com>
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It looks good.

Reviewed-by: Guan Junxiong <guanjunxiong@huawei.com>

On 2017/11/18 8:11, Martin Wilck wrote:
> I don't think anyone can measure latency to 1% accuracy. It's
> better to not even pretend to be able to. 10% should be fine
> even for the most latency-critical environments.
> 
> Signed-off-by: Martin Wilck <mwilck@suse.com>
> ---
>  libmultipath/prioritizers/path_latency.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/libmultipath/prioritizers/path_latency.c b/libmultipath/prioritizers/path_latency.c
> index 9d5397ec1b3a..b8c5bc7c50a4 100644
> --- a/libmultipath/prioritizers/path_latency.c
> +++ b/libmultipath/prioritizers/path_latency.c
> @@ -42,8 +42,9 @@
>  #define DEF_IO_NUM		100
>  
>  #define MAX_BASE_NUM		10
> -#define MIN_BASE_NUM		1.01
> -#define DEF_BASE_NUM		1.5
> +#define MIN_BASE_NUM		1.1
> +// This is 10**(1/4). 4 prio steps correspond to a factor of 10.
> +#define DEF_BASE_NUM		1.77827941004
>  
>  #define MAX_AVG_LATENCY		100000000.	/* Unit: us */
>  #define MIN_AVG_LATENCY		1.		/* Unit: us */
>