A Couchbase profile is used to read and write bucket data in a Couchbase database and can be accessed by workflows using Aggregation, Distributed Storage, or PCC. The profile should not be used to operate on data that has been inserted or updated by external third-party software.
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Item | Desciption |
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External ReferencesImage Removed | Select this menu item to Enable External References in an agent profile field. This can be used to configure the use of the following fields, and the respective external reference keys available: - Bucket Name
- Bucket Password
- Bucket User
- Bucket User Password
- Operation Timeout
- Max Retries
- Retry Interval
- Host
For further information, see 8.10.4 Using External Reference in Agent Profile Fields and 8.10 External Reference Profile. |
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Connectivity TabThe Connectivity tab is displayed by default. Image RemovedImage Added Couchbase profile - Connectivity tab for Couchbase Releases 5.x - 7.x, and 4.x
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| From Couchbase version 5.0, buckets no longer use bucket-level passwords and you must access the bucket using a user and password that you must create in the Couchbase Web Console if it does not already exist. |
The following settings are available in the Connectivity tab: Setting | Description |
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Couchbase Release | Choose between Couchbase release 5.x - 7.x and 4.x. The Bucket Configuration settings are different depending on if you select Couchbase Release 5.x - 7.x or 4.x. Note |
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| If you have upgraded to a Couchbase Release 5.x - 7.x, it is recommended that you select the Couchbase Release 5.x - 7.x version of the Couchbase profile. However, if you have upgraded to a Couchbase Release 5.x - 7.x, but you choose to use the Couchbase Release 4.x version of the Couchbase profile, the user must have the same name as the bucket that you want to use in, and you must enter the mandatory password as the bucket password, which you specify in the Couchbase profile as the Bucket Name and Bucket Password. For further information on creating a bucket, see 11.1 Adding and Removing Buckets. |
| Bucket Name | Enter the bucket that you want to access in Couchbase in this field. | Bucket User | Enter the user who has access rights to the bucket. | User Password | If you have selected Couchbase Release 4.x, you can enter an optional password for the bucket in this field. If you have selected Couchbase Release 5.x - 7.x, enter the password for the user who has access to the bucket.
| Operation Timeout (ms) | Enter the number of milliseconds after which you want Couchbase "CRUD" operations, that is, create, read, update, and delete, to timeout. Setting a lower value than the default 1000 ms may have a positive impact on throughput performance. However, if the value is set too low, indicated by a large number of operation timeouts errors in the EC/ECSA logs, a lower throughput can be expected. As mentioned, this value is used for timing out CRUD operations in Couchbase. This means that sends a request towards Couchbase and if an answer is not returned in time, the operation fails, and is no longer waiting for an answer. | Retry Interval Time (ms) | Enter the time interval, in milliseconds, that you want to wait before trying to read the cluster configuration again after a failed attempt. In other words, in case a request sent to Couchbase returns an unsuccessful answer, the number specified here is the time that waits before retrying the same request. | Max Number Of Retries | Enter the maximum number of retries. This is the number of retries does before treating the Couchbase operation as failed | Cluster Nodes | In this section, add IP addresses/hostnames of at least one of the nodes in the cluster. This address information is used by the Couchbase profile to connect to the cluster at workflow start, and to retrieve the IP addresses of the other nodes in the cluster. If the first node in the list cannot be accessed, the Couchbase profile will attempt to connect to the next one in order. This is repeated until a successful connection can be established. Hence it is not necessary to add all the nodes, but it is good practice to do so for a small cluster. For example, if there are just three nodes, you should add all of them. |
Tip |
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| The Operation Timeout, Retry Interval Time, and Max Number Of Retries settings together with the Advanced tab setting mz.cb.lock.timeout.in.secs, work jointly. To understand how, see the following explanation. If you for example use the lookup function with transaction, a LOCK ERROR means that the lookup failed because there was already a transaction lock held on the object that the lookup was trying to get from Couchbase. That is, the lookup was not able to get a lock on the object. What is most important here is how the communication between and Couchbase works. In case you use the lookup function it works like this: - The lookup function with transaction ID tries to get an object from Couchbase with a lock.
- sends a request to Couchbase to get an object and lock it.
- If the object exists and is not locked, Couchbase creates a lock and sends the answer back with a successful result code and the data. Alternatively, if the object is locked, Couchbase immediately sends an answer with the result LOCK_ERROR. Couchbase does not wait to answer until the lock is released.
This is why the Operation Timeout parameter does not play a crucial role here. The Operation Timeout parameter is only used when Couchbase is stalling and does not send an answer for a long time. Assuming that the object is locked and received answer with LOCK_ERROR, will wait for the amont of time specified in Retry Interval Time and then retry the request towards Couchbase. This process is repeated until Max Number Of Retries is exhausted or the answer contains a successful result code and the object is retrieved from Couchbase. So, if you for example set Retry Interval Time to 100 ms and Max Number of Retries to 10, you get 100 ms * 10 retries = 1000 ms. However, from a MZ perspective, the timeout of 1000 ms is just for a single lookup attempt and not for the whole lookup operation. To clarify, if you get a failed lookupMany with LOCK_ERROR in the system log, it means that the lookup failed because it tried to get an object with a lock but failed after Max Number Of Retries. That is, some other process (or thread) was holding a lock on that particular object for longer than 1000 ms. This is possible if the Advanced tab setting mz.cb.lock.timeout.in.secs is larger than 1000 ms. In other words, you need to decide what is more important - that the operation succeeds or that the operation is fast. |
Management TabThe Management tab contains Cluster Management and Monitoring settings.
Couchbase profile - Management tab The following settings are available in the Management tab: Setting | Description |
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Admin User Name | If you want to create a new bucket that does not exist in your Couchbase cluster, enter the user name that you stated when installing Couchbase in this field. | Admin Password | If you want to create a new bucket that does not exist in your Couchbase cluster, enter the password that you stated when installing Couchbase in this field. | Bucket Size (MB) | Enter the size of the bucket you want to create, in MB. | Number of Replicas | Enter the number of replicas you want to have. | Monitoring - Active | | Frequency (ms) | Obsolete | Failure Count | Obsolete |
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The Couchbase monitoring has become obsolete. Refer to Important Information to find out more. If the bucket you want to access in Couchbase does not exist, the Couchbase profile can be used for creating the bucket in runtime for you, provided that the Admin User Name and Admin Password for your Couchbase cluster have been entered in the Management tab. If the bucket you want to access already exists in your cluster, these two fields do not have to be filled in.
Advanced Tab
In the Advanced tab you can configure additional properties. These can typically be left unchanged in the standard Couchbase configuration.
It is recommended that you change these properties when using the Couchbase profile in Aggregation. For more information about using the Couchbase profile in Aggregation, see Performance Tuning with Couchbase Storage in Aggregation Agent Configuration - Real-Time.
Couchbase profile - Advanced tab
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title | Note on Client Management Timeout |
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If there is a need to control a timeout of any synchronous operation, a system property mz.cb.management.timeout can be used. It should be set for every execution context used to execute a workflow that may require longer timeout. |
See the text in the Properties field for further information about the properties that you can set.
Logging Couchbase Statistics
You can use the property mz.cb.statistics.class
if you want to log Couchbase statistics to file. The default value is com.digitalroute.mimexposer.statistics.NoDbStatistics
.
To enable this property, set the value to com.digitalroute.mimexposer.statistics.MemDbStatistics
or com.digitalroute.mimexposer.statistics.FileDbStatistics
.
If you set the property value to com.digitalroute.mimexposer.statistics.MemDbStatistics
, you can use the MIM agent to send statistics to System Insight. To do this, you must configure a workflow with a MIM agent. For further information, see 9.78.6 MIM Agent.
If you set the property value to com.digitalroute.mimexposer.statistics.FileDbStatistics
, you can use the MIM agent to send statistics to System Insight or you can log to file. If you want to log to file only, you do not require the MIM agent. The log file is stored in $MZ_HOME/log
per bucket, for example <
bucket name>
_couchbase_stats.log,
and the file is flushed every 60 seconds by default. If you want to modify how often the file is flushed, set the property mz.cb.statistics.flush.period.in.seconds
with the required value in the EC.
The Couchbase statistics that you can log include the following:
- Maximum answer time
- Average answer time
- Number of failed CRUDS
- Maximum lock time
- Average lock time
- Number of failed locks
- Number of timed out locks
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