{:#Account metadata}

Metadata about an account that resides in siteXX/info. Examples of metadata include the primary domain, admin username, bandwidth allotment.

{:#API}

An API is the exposed, public features of cod.

{:#Array}

Set of values.

{:#Backtrace}

Reverse order of the call stack

{:#Bandwidth}

Amount of transfer (inbound and outbound) that an account registers over a period. Bandwidth is in bytes unless a unit prefix is specified.

{:#Billing invoice}

An identifier that relates an account or set of accounts to a common billing entity. Billing invoices are stored in billing,invoice account metadata.

{:#Blocking}

Typically used in relation to IO, an operation is blocking if it does not release control of the callstack.

{:#Byte}

An indivisible unit comprised of 8 bits. Bytes are units of measure of how data is stored and transmitted.

{:#Call stack}

Order of operations a program is currently processing. Often call stacks are nested indicating multiple layers of logic to arrive at a point.

{:#Class}

Collection of related code that shares runtime attributes.

{:#Command-line}

Direct server access accessed over terminal. SSH and embedded terminal (KVM) are used to access this mode.

{:#Complex type}

Complex types may store more than one value. In the context of service parameters, a complex type is always an array. Examples: ipinfo,ipaddrs=['64.22.68.1'], aliases,aliases=['domain.com']. ipinfo,namebased=[]

{:#dentry}

A dentry maintains a relationship between a directory - also stored as an inode - and its files. Dentries bind a file or directory name to its metadata (inode).

{:#Function}

Collection of related code.

{:#get_site_id} lit.

get_site_id is a shell helper function to resolve a domain (or addon domain) to its site identifier. Example: get_site_id apiscp.com

{:#/home/virtual}

Account home for all virtual accounts. All accounts follow a siteXX notation with a primary domain symlink for easy access. get_site_id is the preferred utility to resolve a domain to siteXX from the command-line.

{:#inode}

inodes are created by the filesystem to track metadata about files and directories, such as its access times, access rights, and where it is stored. Compare with dentry.

{:#Method}

A function within a class that often inherits attributes about itself.

{:#Load average}

An erroneous definition. See run-queue depth.

{:#Metadata}

Data about data. A common example of this is account metadata that lives in siteXX/info for each account.

{:#null} or None

In context of service values: a service value that is undefined. null is the preferred definition; however, None may be also used owing homage to ApisCP's progenitor, Ensim WEBppliance.

{:#Plan}

Templates consisting of predefined account metadata to be applied to accounts that inherit this plan. Plan assignment is stored in siteinfo,plan account metadata. Plans live in resources/templates/plans. See Plans.md for managing.

{:#Primary domain}

Domain assigned via siteinfo,domain service parameter during account creation. This may be changed at a later date through the API using auth:change-domain.

{:#Run-queue depth}

Often misrepresented as "load average" is the averaged depth of work parcels over a measured unit of time, jiffies. This value is meaningless without evaluating it relative to the number of logical CPUs attached to a server. Run-queue can be high without excessive computation if IO wait is high (indicating blocking IO). Likewise run-queue can hit stratospheric levels necessitating an (ASR)[#automated-system-recovery]

{:#Service name}

A collection of related service parameters; for example, "diskquota" controls how much storage is allotted to an account. Within diskquota are several service parameters that tune aspects relating to diskquota including storage limits and inode limits.

{:#Service parameter}

An attribute within a service name. See service name.

{:#Service value}

Setting for a service parameter. Service values come in simple and complex forms. Certain service parameters have predictable values, such as "enabled" which is 1 or 0. Booleans (true/false) are encoded as 1/0 respectively. Arrays are stored as a complex type.

{#Simple type}

Any value that may be represented as a number, string, or boolean. Simple types cannot hold more than one value. See complex type. Examples: diskquota,quota=4310.55, apache,webuser=apache, siteinfo,enabled=1

{:#siteXX}

An expression that refers to /home/virtual/siteXX where siteXX is the site identifier of an account.

{:#Site identifier}

Internal marker for sites, which is defined on account creation. Site identifier index begins at 1 and the next largest value is assigned. Site identifiers do not change unless the account is deleted, then recreated. Site identifiers may be determined by domain using get_site_id from the command-line. Examples: site12, site1, site999999999..

{:#Site ID identifier}

Numeric component of the Site identifier.

{:#Stack trace}

A frozen call stack associated with bug reports. A stack trace includes the call hierarchy in addition to parameters passed to each method.

{:#Unit}

A measurement quantity. "Bytes", the most common unit referenced, is a measurement of electronic data.