Re: [PATCH 0/6] OvmfPkg, ArmVirtQemu: leaner platform BDS policy for connecting devices

["zhengxiang (A)" <zhengxiang9@huawei.com>]

On 2018/3/14 5:22, Laszlo Ersek wrote:
> Repo:   https://github.com/lersek/edk2.git
> Branch: qemu_bootorder_connect
> 
> Adding tens or hundreds of bootable devices to a QEMU VM config slows
> the OVMF and ArmVirtQemu boots to a crawl, several people have reported
> in the past.
> 
> There are at least two reasons for this (high pflash traffic due to
> heavy nvvar massaging per device, and PCI config space access slowing
> down on QEMU as the number of regions increases). However, part of the
> pain is self-inflicted in our PlatformBootManagerLib instances: we
> connect all bootable devices (for maximum compatibility with the user's
> VM config) even if the user doesn't intend to boot off most of them.
> 
> It's oft repeated that the set of devices connected during boot is
> platform policy, so this series replaces the culprit
> EfiBootManagerConnectAll() calls with a bit smarter algorithm.
> 
> I sought to keep the commit messages under control.
> 

Thanks, Laszlo! It works for booting QEMU VM with 60-virtio-scsi and
24-virtio-net on ARM64.
The boot time reduces from more than one hour to ~90 seconds.

Tested-by: Xiang Zheng <xiang.zheng@linaro.org>

Thanks,
Xiang