Hi
On top of what has been mentioned here (RAID <-> BS aligment, and many other things) I would suggest to look at the last 4/5 slides of a 2018 (disclaimer: my own) London UG presentation http://files.gpfsug.org/presentations/2018/London/14_LuisBolinches_GPFSUG.pdf
It gives a start on
On Fri, 05 Jun 2020 14:24:27 -, "Saula, Oluwasijibomi" said:
> But with the RAID 6 writing costs Vladis explained, it now makes sense why
> the write IO was badly affected...
> Action [1,2,3,4,A] : The only valid responses are characters from this set:
> [1, 2, 3, 4, A]
> Action
(Valdis Kl=?utf-8?Q?=c4=93?=tnieks)
--
Message: 1
Date: Thu, 04 Jun 2020 21:17:08 -0400
From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks"
To: gpfsug main discussion list
Subject: Re: [gpfsug-discuss] Client Latenc
On Thu, 04 Jun 2020 15:33:18 -, "Saula, Oluwasijibomi" said:
> However, I still can't understand why write IO operations are 5x more latent
> than ready operations to the same class of disks.
Two things that may be biting you:
First, on a RAID 5 or 6 LUN, most of the time you only need to
(Stephen Ulmer)
--
Message: 1
Date: Wed, 3 Jun 2020 22:19:49 -0400
From: Stephen Ulmer
To: gpfsug main discussion list
Subject: Re: [gpfsug-discuss] Client Latency and High NSD Server Load
Average
Message-ID:
Content-Type: text/plain; chars
chments/20200603/e839fc73/attachment-0001.html
>
--
Message: 2
Date: Wed, 3 Jun 2020 21:45:05 +
From: "Saula, Oluwasijibomi"
To: "gpfsug-discuss@spectrumscale.org"
Subject: [gpfsug-discuss] Client Latency and High NSD Server L
From the waiters you provided I would guess there is something amiss with some of your storage systems. Since those waiters are on NSD servers they are waiting for IO requests to the kernel to complete. Generally IOs are expected to complete in milliseconds, not seconds. You could look at the
hanks to Ulf, Kristy, Bill, Bob and Ted for their help and guidance in
> getting this going.
>
>
>
> We?re keen to include some user talks and site updates later in the series,
> so please let me know if you might be interested in presenting in this format.
>
>
>
> Simon Thompson
>
&
,
IF the hardware is healthy...
Ed
From: gpfsug-discuss-boun...@spectrumscale.org
on behalf of Saula, Oluwasijibomi
Sent: Wednesday, June 3, 2020 5:45 PM
To: gpfsug-discuss@spectrumscale.org
Subject: [gpfsug-discuss] Client Latency and High NSD Server Load
rg"
Date: 03/06/2020 23:45
Subject: [EXTERNAL] [gpfsug-discuss] Client Latency and High NSD
Server Load Average
Sent by:gpfsug-discuss-boun...@spectrumscale.org
Hello,
Anyone faced a situation where a majority of NSDs have a high load average
and a minority don't?
Also, i
la, Oluwasijibomi"
> Sent by: gpfsug-discuss-boun...@spectrumscale.org
> To: "gpfsug-discuss@spectrumscale.org"
> Cc:
> Subject: [EXTERNAL] [gpfsug-discuss] Client Latency and High NSD Server Load
> Average
> Date: Wed, Jun 3, 2020 5:45 PM
>
>
2
Date: Wed, 3 Jun 2020 21:45:05 +
From: "Saula, Oluwasijibomi"
To: "gpfsug-discuss@spectrumscale.org"
Subject: [gpfsug-discuss] Client Latency and High NSD Server Load
Average
Message-ID:
Content-Type: text/plain; charset="iso-8859-1"
Does the output of mmdf show that data is evenly distributed across your NSDs? If not that could be contributing to your problem. Also, are your NSDs evenly distributed across your NSD servers, and the NSD configured so the first NSD server for each is not the same one?
Hello,
Anyone faced a situation where a majority of NSDs have a high load average and
a minority don't?
Also, is 10x NSD server latency for write operations than for read operations
expected in any circumstance?
We are seeing client latency between 6 and 9 seconds and are wondering if some
14 matches
Mail list logo
