Thresholds and Limits
This page reflects limits and thresholds that apply to AIStor Server.
S3 API limits
| Item | Specification |
|---|---|
| Maximum object size | 50 TiB |
| Minimum object size | 0 B |
Maximum object size per PUT operation |
5 TiB for non-multipart upload 50 TiB for multipart upload |
| Maximum number of parts per upload | 10,000 |
| Part size range | 5 MiB to 5 GiB. Last part can be 0 B to 5 GiB |
| Maximum number of parts returned per list parts request | 10,000 |
| Maximum number of objects returned per list objects request | 1,000 |
| Maximum number of multipart uploads returned per list multipart uploads request | 1,000 |
| Maximum length for bucket names | 63 |
| Maximum length for object names | 1024 |
Maximum length for each / separated segment of an object name |
255 |
| Maximum number of object versions for a unique object | 10000 (Configurable) |
Erasure code limits
| Item | Specification |
|---|---|
| Maximum number of servers per cluster | no limit |
| Minimum number of servers | 1 |
| Minimum number of drives per server when server count is 1 | 1 (for deployments, which do not provide additional reliability or availability) |
| Minimum number of drives per server when server count is 2 or more | 1 |
| Maximum number of drives per server | no limit |
| Read quorum | $$N/2$$ |
| Write quorum | $$(N/2)+1$$ |
Object name limitations
Filesystem and operating system restrictions
Object names in AIStor are restricted primarily by the local operating system and filesystem.
Windows and some other operating systems restrict file systems with certain special characters, such as ^, *, |, \, /, &, ", or ;.
On Unix-like operating systems, objects with a path name of ., .., or / return an error of file access denied.
This list is not exhaustive and may not apply to your operating system and filesystem combination. Consult your operating system vendor or filesystem documentation for a comprehensive list for your situation.
AIStor recommends using a Linux operating system with an XFS based filesystem for production workloads.
Conflicting objects
Applications must assign non-conflicting, unique keys for all objects.
This includes avoiding creating objects where the name can collide with that of a parent or sibling object.
AIStor returns an empty set for LIST operations at the location of the collision.
For example, the following operations create a namespace conflicts
PUT data/invoices/2024/january/vendors.csv
PUT data/invoices/2024/january <- collides with existing object prefix
PUT data/invoices/2024/january
PUT data/invoices/2024/january/vendors.csv <- collides with existing object
While you can perform GET or HEAD operations against these objects, the name collision causes LIST operations to return an empty result set at the /invoices/2024/january path.