Function: packInstructions()

function packInstructions(
  groups,
  options
): Instruction<
  string,
  readonly (AccountLookupMeta<string, string> | AccountMeta<string>)[]
>[][];

Greedily pack instruction groups into the fewest transactions that each stay within Solana's transaction size limit.

Each entry of groups is an atomic group: a single instruction, or an array of instructions that must land together in the same transaction (e.g. a create-account + initialize pair). A group is never split across transactions; groups are filled into a bucket in order until the next group would overflow the size limit, at which point a new bucket is started.

A bucket is bounded by two constraints, and is split whenever the next group would exceed either one:

• Transaction size: determined by compiling each candidate transaction in-memory and measuring its serialized length, so shared accounts (program ids, fee payer, sysvars) are correctly deduplicated — no static estimate and no RPC call.
• Compute units (optional): when a computeUnits estimator is provided, the cumulative estimated compute units of a bucket may not exceed maxComputeUnits.

Parameters

Parameter	Type	Description
groups	( | Instruction<string, readonly (AccountLookupMeta<string, string> | AccountMeta<string>)[]> | Instruction<string, readonly (AccountLookupMeta<string, string> | AccountMeta<string>)[]>[])[]	Atomic instruction groups to pack, in order.
options	PackInstructionsOptions	Packing options (fee payer, reserved instructions, limits).

Returns

Instruction<string, readonly (AccountLookupMeta<string, string> | AccountMeta<string>)[]>[][]

An array of buckets; each bucket is a flat array of instructions for one transaction.

Throws

If a single group cannot fit in one transaction (by size or compute units), since it cannot be split.