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154b2b2296edccb5ed24e829798dacb6195edc11 [fuzz] V3_MAX_VSIZE and effective ancestor/descendant size limits (glozow) a29f1df289cf27c6cbd565448548b3dc1392a9b0 [policy] restrict all v3 transactions to 10kvB (glozow) d578e2e3540e085942001350ff3aeb047bdac973 [policy] explicitly require non-v3 for CPFP carve out (glozow) Pull request description: Opening for discussion / conceptual review. We like the idea of a smaller maximum transaction size because: - It lowers potential replacement cost (i.e. harder to do Rule 3 pinning via gigantic transaction) - They are easier to bin-pack in block template production - They equate to a tighter memory limit in data structures that are bounded by a number of transactions (e.g. orphanage and vExtraTxnForCompact). For example, the current memory bounds for orphanage is 100KvB * 100 = 40MB, and guaranteeing 1 tx per peer would require reserving a pretty large space. History for `MAX_STANDARD_TX_WEIGHT=100KvB` (copied from https://github.com/bitcoin/bitcoin/pull/29873#issuecomment-2115459510): - 2010-09-13 In3df62878c3satoshi added a 100kB (MAX_BLOCK_SIZE_GEN/5 with MBS_GEN = MAX_BLOCK_SIZE/2) limit on new transactions in CreateTransaction() - 2013-02-04 https://github.com/bitcoin/bitcoin/pull/2273 In gavin gave that constant a name, and made it apply to transaction relay as well Lowering `MAX_STANDARD_TX_WEIGHT` for all txns is not being proposed, as there are existing apps/protocols that rely on large transactions. However, it's been brought up that we should consider this for TRUCs (which is especially designed to avoid Rule 3 pinning). This reduction should be ok because using nVersion=3 isn't standard yet, so this wouldn't break somebody's existing use case. If we find that this is too small, we can always increase it later. Decreasing would be much more difficult. ~[Expected size of a commitment transaction](https://github.com/lightning/bolts/blob/master/03-transactions.md#expected-weight-of-the-commitment-transaction) is within (900 + 172 * 483 + 224) / 4 = 21050vB~ EDIT: this is incorrect, but perhaps not something that should affect how we choose this number. ACKs for top commit: sdaftuar: ACK 154b2b2296edccb5ed24e829798dacb6195edc11 achow101: ACK 154b2b2296edccb5ed24e829798dacb6195edc11 instagibbs: ACK 154b2b2296edccb5ed24e829798dacb6195edc11 t-bast: ACK154b2b2296murchandamus: crACK 154b2b2296edccb5ed24e829798dacb6195edc11 Tree-SHA512: 89392a460908a8ea9f547d90e00f5181de0eaa9d2c4f2766140a91294ade3229b3d181833cad9afc93a0d0e8c4b96ee2f5aeda7c50ad7e6f3a8320b9e0c5ae97
Test library
This contains files for the test library, which is used by the test binaries (unit tests, benchmarks, fuzzers, gui tests).
Generally, the files in this folder should be well-separated modules. New code should be added to existing modules or (when in doubt) a new module should be created.
The utilities in here are compiled into a library, which does not hold any state. However, the main file setup_common
defines the common test setup for all test binaries. The test binaries will handle the global state when they
instantiate the BasicTestingSetup (or one of its derived classes).