The Cluster Management Node functionality is optional for SISCI based applications but currently mandatory for SuperSockets operation. The Cluster Management Node will automatically distribute configuration files and simplify diagnostic of the cluster. On the Cluster Management Node, only the user-space service dis_networkmgr (the central Network Manager) needs to be running.

Without the required drivers and services running on a Cluster Node, the node will fail to communicate with other nodes. On the Cluster Nodes, the kernel module dis_kosif (providing operating system dependent functionality to all other kernel modules), the kernel services dis_irm (interconnect resources driver) and dis_sisci (upper level hardware services) and dis_ssocks need to be running. Next to these kernel drivers, the user-space service dis_nodemgr (node manager, which talks to the central Network Manager) needs to be active for configuration and monitoring.

Because the drivers do also appear as services, you can query their status with the usual tools of the installed operating system distribution. I.e., for Red Hat-based Linux distributions, you can do

# service dis_irm status
Dolphin IRM 5.5.0 (  January 10th 2018 ) is running.

Dolphin provides a script dis_services that performs this task for all Dolphin services installed on a machine. It is used in the same way as the individual service command provided by the distribution:

# dis_services status
Dolphin KOSIF 5.5.0 is running
Dolphin PX 5.5.0 (  January 10th 2018 ) is running.
Dolphin IRM 5.5.0 (  January 10th 2018 ) is running.
Dolphin Node Manager is running (pid 3172).
Dolphin SISCI 5.5.0 (  January 10th 2018 ) is running.
Dolphin SuperSockets 5.5.0 "Express Train", January 10th 2018 (built January 10th 
2018) running.

If any of the required services is not running, you will find more information on the problem that may have occurred in the system log facilities. Call dmesg to inspect the kernel messages, and check /var/log/messages for related messages.

To ensure that the cluster is cabled correctly, please perform the PCIe connection test as described in Chapter 4, Initial Installation, Section 3.8.4, “PCIe connection Test”.

The static interconnect test makes sures that all PCIe communication hardware are working correctly by performing a self-test, and determines if the setup and the PCIe routing is correct (matches the actual hardware topology). It will also check all PCIe connections, but this has already been done in the PCIe Connection Test. The tool to perform this test is dis_diag (default location /opt/DIS/sbin/dis_diag).

Running dis_diag on a Cluster Node will perform a self test on the local adapter(s) and list all remote adapters that this adapter can see via the PCI Express interconnect. This means, to perform the static interconnect test on a full cluster, you will basically need to run dis_diag on each Cluster Node and see if any problems with the adapter are reported, and if the adapters in each Cluster Node can see all remote adapters installed in the other Cluster Nodes.

Normally you should invoke dis_diag with no arguments, and it will do a general test and only show the most interesting information. Advanced users may want to enable the full verbose mode by using the -V 9 command line option:

	  dis_diag -V 9	
	

The -V 9 option will generate a lot of information, some parts of the information requires knowledge about the PCIe chipset and the PCIe specification in general. The diagnostic module will collect various usage and error information over time. This can be cleared by using the -clear command line option:

	  dis_diag -clear	
	

An example output of dis_diag for a Cluster Node which is part of a 2 node cluster and using one PXH830 adapter per Cluster Node looks like this:

[root@Hetty ~]# /opt/DIS/sbin/dis_diag 
================================================================================
  Dolphin diagnostic tool --  dis_diag version 5.5.0 ( Thu Jan 10th 16:23:13 CET 2018 )
================================================================================

dis_diag compiled in 64 bit mode
Driver : Dolphin IRM (GX) 5.5.0.0 Jan 10th 2018 (rev unknown)
Date   : Wed Feb  1 14:34:26 CET 2018
System : Linux Hetty 3.10.0-514.6.1.el7.x86_64 #1 SMP Wed Jan 18 13:06:36 UTC 2017 
         x86_64 x86_64 x86_64 GNU/Linux

Number of configured local adapters found: 1

Adapter 0 > Type                       : PXH830
            NodeId                     : 4
            Serial number              : PXH830-BC-000116
            PXH chip family            : PLX_DRACO_2  
            PXH chip vendorId          : 0x10b5  
            PXH chip device            : 0x8733  
            PXH chip revision          : 0xCA 
            EEPROM version NTB mode    : 05  
            EEPROM vendor info         : 0x0000  
            Firmware version           : 05.01
            Card revision              : BC
            Topology type              : Direct 2 nodes
            Topology Autodetect        : No
            Number of enabled links    : 1
            Max payload size (MPS)     : 256 
            Multicast group size       : 2 MB 
            Prefetchable memory size   : 32768 MB (BAR2)
            Non-prefetchable size      : 64 MB (BAR4)
            Clock mode slot            : Port 
            Clock mode link            : Global 
            PCIe slot state            : x16, Gen3 (8 GT/s) 
            PCIe slot capabilities     : x16, Gen3 (8 GT/s) 

*************************  PXH ADAPTER 0 LINK 0 STATE  *************************

            Link 0 uptime              : 91371 seconds
            Link 0 state               : ENABLED
            Link 0 state               : x16, Gen3 (8 GT/s) 
            Link 0 required            : x16, Gen3 (8 GT/s)
            Link 0 capabilities        : x16, Gen3 (8 GT/s)
            Link 0 cable inserted      : 1 
            Link 0 active              : 1 
            Link 0 configuration       : NTB

****************************  PXH ADAPTER 0 STATUS  ****************************

            Chip temperature           : 87 C 
            Board temperature          : 50 C 

***************  PXH ADAPTER 0, PARTNER INFORMATION FOR LINK 0  ***************
 
            Partner adapter type       : PXH830
            Partner serial number      : PXH830-000117
            Partner link no            : 0
            Partner number of ports    : 1
 
*****************************  TEST OF ADAPTER 0  *****************************

OK: PXH chip alive in adapter 0.
OK: Link alive in adapter 0.
==> Local adapter 0 ok.

************************  TOPOLOGY SEEN FROM ADAPTER 0  ************************

Adapters found: 2
----- List of all nodes found:

Nodes detected:   0004  0008 

***********************  SESSION STATUS FROM ADAPTER 0  ***********************

Node 4: Session valid
Node 8: Session valid

----------------------------------
dis_diag discovered 0 note(s).
dis_diag discovered 0 warning(s).
dis_diag discovered 0 error(s).
TEST RESULT: *PASSED*
	

The static interconnect test passes if dis_diag delivers TEST RESULT: *PASSED* and reports the same topology (remote adapters) on all Cluster Nodes.

While the static interconnect test sends very a few packets over the links to probe remote nodes, the Interconnect Load Test puts significant stress on the interconnect and observes if any data transmissions have to be retried due to link errors. This can happen if cables are not correctly connected, i.e. plugged in without connector latches locking correctly. Before running this test, make sure your cluster is connected and configured correctly by running the tests described in the previous sections.

Once the correct installation and setup and the basic functionality of the interconnect have been verified, it is possible to perform a set of low-level benchmarks to determine the base-line performance of the interconnect without any additional software layers. The tests that are relevant for this are scibench2 (streaming remote memory PIO access performance), scipp (request-response remote memory PIO write performance), dma_bench (streaming remote memory DMA access performance) and intr_bench (remote interrupt performance).

All these tests need to run on two Cluster Nodes (A and B) and are started in the same manner:

To simply gather all relevant low-level performance data, the script sisci_benchmarks.sh can be called in the same way. It will run all of the described tests.