Here is a document from Red Hat: Storage Management for the Oracle Database on Red Hat Enterprise Linux 6: Using ASM With or Without ASMLib

https://access.redhat.com/sites/default/files/oracle_on_rhel_with_or_without_asm_asmlib_0.pdf

Oracle introduced ASMLib in 2004 to provide Oracle workloads on Linux with performance and stability comparable to equivalent workloads on UNIX. ASMLib addressed deficiencies – including a lack of async and direct I/O -- that existed in the 2.4 Linux kernel.

The Linux community addressed these deficiencies in the 2.6 Linux kernel with the addition of udev and device-mapper multipath which together with LVM provided native multipathing, scalable native volume management, and persistent device naming. Additionally, the 2.6 Linux kernel added tools for handling large numbers of disks, especially SAN-attached disks.

Thanks for your inforamtion.

Could I take it in this way, pre kernel 2.6, ASMLIB is better, after that either is good?

I am all set, your input is appreciated.

As ASM is out-of-band (i.e. the ASM instance, ASMLib etc) are not in the I/O path, I guess ASMlib has no direct influence in performance (except that they might make it easier to enforce best practices that would also be possible without, it if configured correctly).

Oracle recommends using ASM with ASMLib together for better manageability and persistent device naming.

Note that Oracle makes no claims that ASM with ASMLib delivers performance benefits over ASM without ASMLib after 2.6 Linux kernel.