Lustre 1.6 Operations Manual

31.2.3 QSW LND
The QSW LND (qswlnd) is connection-less and, therefore, does not need the
acceptor. It is limited to a single instance, which uses all Elan "rails" that are present
and dynamically load balances over them.
The address-with-network is the node's Elan ID. A specific interface cannot be
selected in the "networks" module parameter.
Variable
tx_maxcontig
(1024)
mtxmsgs
(8)
nnblk_txmsg
(512 with a 4K page
size, 256 otherwise)
nrxmsg_small
(256)
ep_envelopes_small
(2048)
nrxmsg_large
(64)
ep_envelopes_large
(256)
optimized_puts
(32768,W)
optimized_gets
(1,W)
Description
Integer that specifies the maximum message payload (in bytes) to
copy into a pre-mapped transmit buffer
Number of "normal" message descriptors for locally-initiated
communications that may block for memory (callers block when
this pool is exhausted).
Number of "reserved" message descriptors for communications
that may not block for memory. This pool must be sized large
enough so it is never exhausted.
Number of "small" receive buffers to post (typically everything
apart from bulk data).
Number of message envelopes to reserve for the "small" receive
buffer queue. This determines a breakpoint in the number of
concurrent senders. Below this number, communication attempts
are queued, but above this number, the pre-allocated envelope
queue will fill, causing senders to back off and retry. This can have
the unfortunate side effect of starving arbitrary senders, who
continually find the envelope queue is full when they retry. This
parameter should therefore be increased if envelope queue
overflow is suspected.
Number of "large" receive buffers to post (typically for routed bulk
data).
Number of message envelopes to reserve for the "large" receive
buffer queue. For more information on message envelopes, see the
ep_envelopes_small option (above).
Smallest non-routed PUT that will be RDMA’d.
Smallest non-routed GET that will be RDMA’d.
31-10 Lustre 1.6 Operations Manual • September 2008