Re: [PATCH] scsi: megaraid_sas: disabled shared host tagset feature by default

[John Garry <john.g.garry@oracle.com>]

On 11/03/2024 08:54, mengfanhui wrote:
> By default, the host_tagset_enable feature is disabled，Fio performance
> has improved significantly
> 
> fio test command:
> sudo fio -filename=/fio_test -direct=1 -iodepth 32 -thread -rw=write -ioengine=libaio
> -bs=4K -size=5120M -runtime=600 -numjobs=$CPUN -group_reporting -name=**.result >> **.result
> 
> The test data results bw  are as follows：
>                v6.8_kernel       v6.8_kernel_disable_host_tagset
> 4k randwrite     375                     642
> 4k randread      210                     784
> 4k  write        306                     387
> 4k  read         435                     2457
> 128k write       355                     380
> 128k read        976                     3665
> 1M   read        415                     3122
> 

There are some huge differences in those numbers. Can you find out what 
is going on?

> Signed-off-by: mengfanhui <mengfanhui@kylinos.cn>
> ---
>   drivers/scsi/megaraid/megaraid_sas_base.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
> index 3d4f13da1ae8..da19c4c07f2f 100644
> --- a/drivers/scsi/megaraid/megaraid_sas_base.c
> +++ b/drivers/scsi/megaraid/megaraid_sas_base.c
> @@ -123,9 +123,9 @@ MODULE_PARM_DESC(poll_queues, "Number of queues to be use for io_uring poll mode
>   		"High iops queues are not allocated &\n\t\t"
>   		);
>   
> -int host_tagset_enable = 1;
> +int host_tagset_enable;
>   module_param(host_tagset_enable, int, 0444);
> -MODULE_PARM_DESC(host_tagset_enable, "Shared host tagset enable/disable Default: enable(1)");
> +MODULE_PARM_DESC(host_tagset_enable, "Shared host tagset enable/disable Default: disable(0)");
>   
>   MODULE_LICENSE("GPL");
>   MODULE_VERSION(MEGASAS_VERSION);