Re: [PATCH] RDMA/core: reduce IB_POLL_BATCH constant

[Bart Van Assche]

On Tue, 2018-02-20 at 21:59 +0100, Arnd Bergmann wrote:
>  /* # of WCs to poll for with a single call to ib_poll_cq */
> -#define IB_POLL_BATCH			16
> +#define IB_POLL_BATCH			8

The purpose of batch polling is to minimize contention on the cq spinlock.
Reducing the IB_POLL_BATCH constant may affect performance negatively. Has
the performance impact of this change been verified for all affected drivers
(ib_srp, ib_srpt, ib_iser, ib_isert, NVMeOF, NVMeOF target, SMB Direct, NFS
over RDMA, ...)?

Bart.