[GAIAPLAT-425] Change locator size to 32 bits #1380
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| @@ -119,6 +119,9 @@ struct hash_node_t | |||
| struct log_record_t | |||
| { | |||
| gaia_locator_t locator; | |||
| // Locators are now 4 bytes, so we need to add 4 bytes of padding to keep | |||
| // total size at 16 bytes. | |||
| uint32_t reserved; | |||
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Why don't we place this padding at the end?
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Also, I'd shorten the comment to the essential: "We need 4 bytes of padding to maintain total size at 16 bytes".
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Why don't we place this padding at the end?
It's not essential, but I prefer to align the two offsets on an 8-byte boundary, in case I wanted to treat them atomically at some point.
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We need 4 bytes of padding to maintain total size at 16 bytes
OK, I was referencing the locator size change itself, but I guess code comments shouldn't reference changes unless absolutely necessary. Updated comment.
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I prefer to align the two offsets on an 8-byte boundary, in case I wanted to treat them atomically at some point.
In that case, can you add a comment about this? Although frankly, why wouldn't you defer any fancy ordering until it's actually needed? If you'd even need something like this, you could always re-arrange the fields at that time.
This is a very old task that's been repeatedly deferred, but it's finally necessary for my current table scan index changes (I need to add a metadata word to the locator list node structure, which must be updated atomically with the locator-valued "next" pointer, so the whole thing must fit into 8 bytes). Because locators have always been de facto 32-bit-valued, there are no changes required other than updating type definitions.