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Hi Kevin,</div>
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Yes. Single OST</div>
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-Prasad</div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Harms, Kevin <harms@alcf.anl.gov><br>
<b>Sent:</b> Tuesday, June 9, 2026 4:11:12 PM<br>
<b>To:</b> lustre-discuss@lists.lustre.org <lustre-discuss@lists.lustre.org>; Ganji, Prasadreddy <Prasadreddy.Ganji@kla.com><br>
<b>Subject:</b> [EXTERNAL]: Re: Terrible BW via lustre network</font>
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<pre style="font-family:sans-serif; font-size:100%; white-space:pre-wrap; word-wrap:break-word">
You said you have 1 OSS.. do you also have 1 OST? or more than one? if more than one, are you using more than one?
kevin
________________________________________
From: lustre-discuss <lustre-discuss-bounces@lists.lustre.org> on behalf of Ganji, Prasadreddy via lustre-discuss <lustre-discuss@lists.lustre.org>
Sent: Tuesday, June 9, 2026 2:40 PM
To: lustre-discuss@lists.lustre.org
Subject: [lustre-discuss] Terrible BW via lustre network
Hello folks, I'm relatively new to Lustre and experimenting. I'm seeing significantly lower throughput than expected on the client side and would appreciate any suggestions. Environment: OS: Rocky 8.\u200a10 Lustre: 2.\u200a15.\u200a6 ZFS: 2.\u200a1.\u200a15-1 Cluster Layout
Hello folks,
I'm relatively new to Lustre and experimenting. I'm seeing significantly lower throughput than expected on the client side and would appreciate any suggestions.
Environment:
OS: Rocky 8.10
Lustre: 2.15.6
ZFS: 2.1.15-1
Cluster Layout (3 nodes):
IB HDR 200G connection b/w all 3 nodes are good.
1 Lustre server (combined MGS/MDS)
1 OSS (60 HDDs configured as a single dRAID3 pool, one vdev)
1 Client (using the same Lustre server image)
Problem:
Raw bandwidth per drive: ~250 MB/s
ZFS pool raw throughput (local): 5\u20135.5 GB/s
Lustre client mount throughput: <300 MB/s
There's a massive gap between what the pool can deliver locally and what the client sees over Lustre. I'd appreciate any guidance on what might be limiting performance \u2014 whether it's network, OST count, stripe configuration, ZFS tuning, or something else entirely.
Thanks,
Prasad
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