From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Gunthorpe Subject: Re: [PATCH 1/2] net/mlx5: increase async EQ to avoid EQ overrun Date: Mon, 5 Feb 2018 11:09:04 -0700 Message-ID: <20180205180904.GB11446@mellanox.com> References: <1517840992-29813-1-git-send-email-maxg@mellanox.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1517840992-29813-1-git-send-email-maxg-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Max Gurtovoy Cc: linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, sagi-NQWnxTmZq1alnMjI0IkVqw@public.gmane.org, vladimirk-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org List-Id: linux-rdma@vger.kernel.org On Mon, Feb 05, 2018 at 04:29:51PM +0200, Max Gurtovoy wrote: > Currently the async EQ has 256 entries only. It might not be big enough > for the SW to handle all the needed pending events. For example, in case > of many QPs (let's say 1024) connected to a SRQ created using NVMeOF target > and the target goes down, the FW will raise 1024 "last WQE reached" events > and may cause EQ overrun. Increase the EQ to more reasonable size, that beyond > it the FW should be able to delay the event and raise it later on using internal > backpressure mechanism. If the firmware has an internal backpressure meachanism then why would we get a EQ overrun? Do we need to block adding too many QPs to a SRQ as well or something like that? Jason -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html