performance - Storing a 32 byte object, on Ivy Bridge? -

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i trying find out whether, on ivy bridge, possible write 256-bit object consists of various data types (int, double, float etc)?

i have had @ intel manual , ctrl+f "32-byte" results discussing 256-bits of same data type (so 4x doubles or 8x floats etc).

i doing part of lock-free design ensure data consistency- load 256 bits of data together, extract each of various components separately.

i did web search, , appears intel not guarantee 32 byte write atomic. found this suggests not regular 8 byte writes guaranteed atomic.

intel provides compare , exchange 8 byte instruction atomic.

bottom line think need take approach.

edit: forgot x86 lock prefix. looking @ this, says byte memory operations guaranteed atomic, while larger operations not unless lock prefix used on read/write instruction.


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