lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Date:	Tue, 14 Oct 2014 03:49:52 -0400
From:	Rik van Riel <>
To:	Peter Zijlstra <>
Subject: Re: [PATCH RFC 1/5] sched,numa: build table of node hop distance

On 10/14/2014 02:47 AM, Peter Zijlstra wrote:
> On Sun, Oct 12, 2014 at 09:28:04AM -0400, Rik van Riel wrote:
>> On 10/12/2014 09:17 AM, Peter Zijlstra wrote:
>>> On Wed, Oct 08, 2014 at 03:37:26PM -0400, wrote:
>>>> +	sched_domains_numa_hops = kzalloc(sizeof(int) * nr_node_ids * nr_node_ids, GFP_KERNEL);
>>>> +	if (!sched_domains_numa_hops)
>>>> +		return;
>>> That's potentially a _BIG_ table (1M for a 512 node system).
>>> The node_distance has magic allocations and is of u8 size, is there any
>>> way we can re-use node_distance and avoid a second O(n^2) allocation?
>> You are right, this should be a u8 at the least.
>> Beyond that, I am not convinced that merging things into
>> the same array is worthwhile, since (IIRC) nr_node_ids
>> should be set to the actual number of nodes on the system
>> by then.
> The thing is, it looks like all you do is compare hop distance, and the
> order of the hop distances is the exact same order as the regular numa
> distance. I could not find a place where you use the actual hop value.

I use the actual hop distances when doing the scoring
for glueless mesh topologies, in patch 4/5.

> So if all you're interested in is the relative ordering, that should be
> the same for both.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

Powered by blists - more mailing lists