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charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Proofpoint-GUID: sfYS3D38rGkGtu1kizH2zdBsCQQ3w8WX X-Authority-Analysis: v=2.4 cv=JayxbEKV c=1 sm=1 tr=0 ts=699f85f5 cx=c_pps a=UObrlqRbTUrrdMEdGJ+KZA==:117 a=UObrlqRbTUrrdMEdGJ+KZA==:17 a=IkcTkHD0fZMA:10 a=HzLeVaNsDn8A:10 a=VkNPw1HP01LnGYTKEx00:22 a=Mpw57Om8IfrbqaoTuvik:22 a=GgsMoib0sEa3-_RKJdDe:22 a=wlqWKYu9QVe-UJ9kQ2YA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMjI1MDIyNCBTYWx0ZWRfXyD6XZf+TVue1 fx8Os3MXWW4V1ghT0S2GVDepVEYwDk+eixQAklUtqSo71t7fuwsEvXmzKf3QbT+v5xVPAvf01FQ +zqGZfOP3RLDv2SQ7a2lColExd4bCDPqu+xR9JEWMYtIlsNG1vK4aDJVLHNB5/i28xmgx8XnY00 wcXWPZQFQ2qRROvOOYO+OQXXmLwCkULC+pJ4zvHhgSHdNLJVbcfc8uzUmQiplrShS2vsGb1MvyZ PgxYIXscFp+BEUM0DSfX9JWmDBYWZ2LqgIHi9oyEgyDnusVfP4InqvVypKCWKdWcsX0K2G1tOQW 3c3ACeE/8jqaeWgpFWhTr6SbqOzoX2yuMnilNs/Gy0dXxvuSt3+GRNSOOTHhfeDBr3vds2CQTlv xTb0xluykiwts1J6tv+yaaRL6Xh5ssXtbySCQ5cfeCzLwQ6q/FAVhIYsF97nynHLqOR6Tvkp8Vp 6xZ2xpbXuTN2xNDBeiA== X-Proofpoint-ORIG-GUID: sfYS3D38rGkGtu1kizH2zdBsCQQ3w8WX X-HPE-SCL: -1 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-02-25_04,2026-02-25_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 suspectscore=0 phishscore=0 malwarescore=0 clxscore=1015 bulkscore=0 spamscore=0 impostorscore=0 adultscore=0 priorityscore=1501 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2601150000 definitions=main-2602250224 On Wed, Feb 25, 2026 at 02:55:58PM -0800, Tim Chen wrote: > On Wed, 2026-02-25 at 23:30 +0100, Peter Zijlstra wrote: > > On Wed, Feb 25, 2026 at 01:37:11PM -0800, Tim Chen wrote: > > > On Wed, 2026-02-25 at 17:32 +0100, Peter Zijlstra wrote: > > > > On Wed, Feb 25, 2026 at 04:44:09PM +0100, Peter Zijlstra wrote: > > > > > > > > > Yes, so this assumes that all u sized clusters on the trace are similar > > > > > and 'sane' without verification. > > > > > > > > That gave me an idea; how's this then? > > > > > > Sorry I was sick for a few days. Just catching up on this > > > thread here. I think your patch takes care of both GNR SNC-3  > > > with 3 compute dies (with non-symmetric remote > > > distances) and generic SNC-2 with 2 dies (symmetric > > > distances) very well. > > > > > > Minor suggestion below for the patch. > > > > > > Will ask the original GNR teams with the problem to try > > > it out. > > > > Since HPE can obviously have a sane SLIT table; why can't we simply > > claim the SLIT table they had is broken and needs fixing? > > From what I can see HPE seems to use SNC-2 variant of GNR so the SLIT > is symmetric. Yes, and the SKUs that don't support SNC. The SKUs that support SNC-3 are limited to 2 packages. > Unfortunately in the topology for the 2 socket GNR that has 3 dies, there > are truly unsymmetric paths from between die A to die B between remote > sockets from what I'm told. What does MLC look like? > > Also, is there really no enumeration of the SNC mode available; must we > > really divinate? > > Let me dig into that a bit. I was also thinking with that information, > it will make the code a lot simpler.