[illumos-Developer] Question about zio_taskqs in spa.c

[WenChun Cheng]

Hi all,

Can someone please explain the reasons behind the following
configuration? Especially on the ZTI_FIX(8) for read and ZTI_FIX(100)
for free.

/*
  * Define the taskq threads for the following I/O types:
  * 	NULL, READ, WRITE, FREE, CLAIM, and IOCTL
  */
const zio_taskq_info_t zio_taskqs[ZIO_TYPES][ZIO_TASKQ_TYPES] = {
  /* ISSUE ISSUE_HIGH INTR INTR_HIGH */
  { ZTI_ONE, ZTI_NULL, ZTI_ONE, ZTI_NULL },
  { ZTI_FIX(8), ZTI_NULL, ZTI_BATCH, ZTI_NULL },
  { ZTI_BATCH, ZTI_FIX(5), ZTI_FIX(8), ZTI_FIX(5) },
  { ZTI_FIX(100), ZTI_NULL, ZTI_ONE, ZTI_NULL },
  { ZTI_ONE, ZTI_NULL, ZTI_ONE, ZTI_NULL },
  { ZTI_ONE, ZTI_NULL, ZTI_ONE, ZTI_NULL },
};

Thanks,
--Wenchun Cheng