This post provides a comprehensive list of all configuration options available in vdsm.conf for vdsm. The file vdsm.conf.sample includes a commented list of all available options in vdsm.conf.

This is provided by vdsm package. You can find it at:

/usr/share/doc/vdsm-4.30.33/vdsm.conf.sample

For example, check the configurable VDSM tunables for volumes:

$ less /usr/share/doc/vdsm-4.30.33/vdsm.conf.sample |grep -i -C2 volume

# How often should we check drive watermark on block storage for
# automatic extension of thin provisioned volumes (seconds).
# vm_watermark_interval = 2

--
# Together with volume_utilization_chunk_mb, set the minimal free

# space before a thin provisioned block volume is extended. Use lower
# values to extend earlier.
# volume_utilization_percent = 50

# Size of extension chunk in megabytes, and together with
# volume_utilization_percent, set the free space limit. Use higher
# values to extend in bigger chunks.
# volume_utilization_chunk_mb = 1024

# Use events, instead of polling, to check the write threshold on
--
# enable_block_threshold_event = true

# How often should the volume size be checked (seconds).
# vol_size_sample_interval = 60

--
# iscsi_default_ifaces = default

# Whether to use the volume leases or not.
# use_volume_leases = false