Install tntapi¶

The tntapi component connects the Tarantool database and the facenapi component, transferring search results from the database to facenapi for further processing. To increase search speed, multiple tntapi shards can be created on each Tarantool host. Their running concurrently leads to a remarkable increase in performance. Each shard can handle up to approximately 10,000,000 faces. In the case of standalone deployment, you need only one shard (created by default), while in a cluster environment the number of shards has to be calculated depending on several parameters (see below).

Install tntapi standalone¶

Install and configure the tntapi component as follows:

Install tntapi. Tarantool will be installed automatically along with it.

sudo apt-get update
sudo apt-get install findface-tarantool-server

Disable the Tarantool example service autostart and stop the service.

sudo systemctl disable tarantool@example && sudo systemctl stop tarantool@example

For a small-scale project, the tntapi shard created by default (tarantool@FindFace) would suffice as 1 shard can handle up to 10,000,000 faces. Configuration settings of the default shard are defined in the file /etc/tarantool/instances.enabled/FindFace.lua. We strongly recommend you not to add or edit anything in this file, except the maximum memory usage (memtx_memory), the NTLS IP address required for the tntapi licensing, and the remote access setting. The maximum memory usage should be set in bytes, depending on the number of faces the shard handles, at the rate roughly 1280 byte per face.

Open the configuration file:
```
sudo vi /etc/tarantool/instances.enabled/FindFace.lua
```
Edit the value due to the number of faces the shard handles. The value 1.2*1024*1024*1024 corresponds to 1,000,000 faces:
```
memtx_memory = 1.2 * 1024 * 1024 * 1024,
```
Specify the NTLS IP address if NTLS is remote:
```
FindFace.start(“127.0.0.1”, 8001, {license_ntls_server=“192.168.113.2:3133”})
```
With standalone deployment, you can access Tarantool by default only locally (127.0.0.1). If you want to access Tarantool from a remote host, either specify the remote host IP address in the FindFace.start section, or change 127.0.0.1 to 0.0.0.0 there to allow access to Tarantool from any IP address. In the case-study below, you allow access only from 192.168.113.10:
```
FindFace.start("192.168.113.10", 8001, {license_ntls_server=“192.168.113.2:3133”})
```
Now you allow access from any IP address:
```
FindFace.start("0.0.0.0", 8001, {license_ntls_server=“192.168.113.2:3133”})
```

Configure the tntapi shard to autostart and start the shard.

sudo systemctl enable tarantool@FindFace && sudo systemctl start tarantool@FindFace

Retrieve the shard status. The command will return a service description, a status (should be Active), path and running time.
```
sudo systemctl status tarantool@FindFace
```
Tip

You can view the tntapi logs by executing:
```
sudo tail -f /var/log/tarantool/FindFace.log
```
The tntapi.json file containing the tntapi shard parameters is automatically installed along with tntapi into the /etc/ folder.

Important

You will have to uncomment the path to tntapi.json when configuring network.

Install tntapi cluster¶

Install and configure the tntapi component as follows:

Install tntapi on designated hosts. Tarantool will be installed automatically along it.
```
sudo apt-get update
sudo apt-get install findface-tarantool-server
```
Create tntapi shards on each tntapi host. To learn how to shard, let’s consider a case-study of a cluster environment containing 4 database hosts. We’ll create 4 shards on each.
Important

When creating shards in large installations, observe the following rules:
1. 1 tntapi shard can handle approximately 10,000,000 faces.
2. The number of shards on a single host should not exceed the number of its physical processor cores minus 1.
Disable the Tarantool example service autostart and stop the service. Do so for all the 4 hosts.
```
sudo systemctl disable tarantool@example && sudo systemctl stop tarantool@example
```
Disable the shard created by default. Do so for all the 4 hosts.
```
sudo systemctl disable tarantool@FindFace
```
Write a bash script shard.sh that will automatically create configuration files for all shards on a particular host. Do so for the 4 hosts. Use the following script as a base for your own code. The exemplary script creates 4 shards listening to the ports: tntapi 33001..33004 and http 8001..8004.
Important

The script below creates configuration files based on the default configuration settings stored in the file /etc/tarantool/instances.enabled/FindFace.lua. We strongly recommend you not to add or edit anything in the default file, except the maximum memory usage (memtx_memory) and the NTLS IP address required for the tntapi licensing. The maximum memory usage should be set in bytes for each shard, depending on the number of faces a shard handles, at the rate roughly 1280 byte per face.

Open the configuration file:
```
sudo vi /etc/tarantool/instances.enabled/FindFace.lua
```
Edit the value due the number of faces a shard handles. The value 1.2*1024*1024*1024 corresponds to 1,000,000 faces:
```
memtx_memory = 1.2*1024*1024*1024,
```
Specify the NTLS IP address if NTLS is remote:
```
FindFace.start(“127.0.0.1”, 8001, {license_ntls_server=“192.168.113.2:3133”})
```
```
#!/bin/sh
set -e

for I in `seq 1 4`; do
       TNT_PORT=$((33000+$I)) &&
       HTTP_PORT=$((8000+$I)) &&
       sed "
               s#/opt/ntech/var/lib/tarantool/default#/opt/ntech/var/lib/tarantool/shard_$I#g;
               s/listen = .*$/listen = '127.0.0.1:$TNT_PORT',/;
               s/\"127.0.0.1\", 8001,/\"0.0.0.0\", $HTTP_PORT,/;
       " /etc/tarantool/instances.enabled/FindFace.lua > /etc/tarantool/instances.enabled/FindFace_shard_$I.lua;

       mkdir -p /opt/ntech/var/lib/tarantool/shard_$I/snapshots
       mkdir -p /opt/ntech/var/lib/tarantool/shard_$I/xlogs
       mkdir -p /opt/ntech/var/lib/tarantool/shard_$I/index
       chown -R tarantool:tarantool /opt/ntech/var/lib/tarantool/shard_$I
       echo "Shard #$I inited"
done;
```
Tip

Download the exemplary script.
Run the script from the home directory.
```
sudo sh ~/shard.sh
```

Check the configuration files created.

ls /etc/tarantool/instances.enabled/

##example.lua FindFace.lua FindFace_shard_1.lua FindFace_shard_2.lua FindFace_shard_3.lua FindFace_shard_4.lua

Launch all the 4 shards. Do so on each host.

for I in `seq 1 4`; do sudo systemctl enable tarantool@FindFace_shard_$I; done;
for I in `seq 1 4`; do sudo systemctl start tarantool@FindFace_shard_$I; done;

Retrieve the shards status.

sudo systemctl status tarantool@FindFace*

You should get the following output:

tarantool@FindFace_shard_3.service - Tarantool Database Server
Loaded: loaded (/lib/systemd/system/tarantool@.service; disabled; vendor preset: enabled)
Active: active (running) since Tue 2017-01-10 16:22:07 MSK; 32s ago
...
tarantool@FindFace_shard_2.service - Tarantool Database Server
Loaded: loaded (/lib/systemd/system/tarantool@.service; disabled; vendor preset: enabled)
Active: active (running) since Tue 2017-01-10 16:22:07 MSK; 32s ago
...
tarantool@FindFace_shard_1.service - Tarantool Database Server
Loaded: loaded (/lib/systemd/system/tarantool@.service; disabled; vendor preset: enabled)
Active: active (running) since Tue 2017-01-10 16:22:07 MSK; 32s ago
...
tarantool@FindFace_shard_4.service - Tarantool Database Server
Loaded: loaded (/lib/systemd/system/tarantool@.service; disabled; vendor preset: enabled)
Active: active (running) since Tue 2017-01-10 16:22:07 MSK; 32s ago
...

Tip

You can view the tntapi logs by executing:

sudo tail -f /var/log/tarantool/FindFace_shard_{1,2,3,4}.log

On the findface-facenapi host, create a file tntapi_cluster.json containing the addresses and ports of all the shards. Distribute available shards evenly over ~1024 cells in one line. Click here to see the file for 4 hosts with 4 shards on each.
Tip

You can create tntapi_cluster.json as follows:
1. Create a file that lists all the shards, each shard with a new line (click here to view the example).
  
  sudo vi s.txt
2. Run the script below (click here to view the script). As a result, a new file tntapi_cluster.json will be created and contain a list of all shards distributed evenly over 1024 cells.
cat s.txt | perl -lane 'push(@s,$_); END{$m=1024; $t=scalar @s;for($i=0;$i<$m;$i++){$k=int($i*$t/$m); push(@r,"\"".$s[$k]."\"")} print "[[".join(", ",@r)."]]"; }' > tntapi_cluster.json
Move tntapi_cluster.json to the directory /etc/.

Important

You will have to uncomment and specify the path to tntapi_cluster.json when configuring network.