Ripple Faces Major Bug in AMM Update; What You Need to Know

In a new tweet, RippleX reported an issue with the AMM amendment, which adds Automated Market Maker (AMM) capabilities to the XRP Ledger.

On Jan. 31, the AMM amendment received a majority vote and may be activated on the mainnet within 14 days.

In its tweet, RippleX states that it discovered during extended integration testing that the AMM does not function as planned over time, an issue that might prohibit multiple AMM transactions from executing in the same ledger. As a result, it has proposed and is reviewing a fix.

1/ In extended integration testing to ensure the AMM performs as intended over time, we identified an issue that could prevent multiple AMM txs from executing in the same ledger. We have proposed and are reviewing a fix: https://t.co/MPMKuI8dDK

— RippleX (@RippleXDev) February 1, 2024

That issue arises in an edge case where the trading fee is less than 0.01%; certain AMM transactions must wait for one ledger (3-5 seconds) before being executed.

It explains further that accessing specific default fields belonging to AMM inner objects may prevent a transaction from succeeding in certain cases. When a ledger contains “AMM create” and the trading fee is less than 0.01%, AMM transactions must wait for the next ledger (3-5 seconds) to succeed.

RippleX noted that there was no issue if the trading fee was greater than or equal to 0.01%. However, if the trading fee is less than 0.01%, this issue arises.

The proposed fix provides a way for an inner object to correctly identify default fields and is implemented in both the core ledger and AMM code.

In all circumstances, AMM behavior is accurate, and the issue does not affect ledger stability. Nonetheless, the fix can eliminate edge cases and ensure the AMM always performs as expected.

The knowledge of the AMM amendment bug has not deterred support for it in any way.

XRP Scan and XRP Ledger explorer and blockchain analysis platform express support for the AMM amendment, citing the low impact and non-breaking nature of the bug as well as a known workaround.

As reported, RippleX announced the release of rippled (XRP Ledger Server) Version 2.0.1, a software upgrade that introduced several improvements and bug fixes during the week. The rippled v2.0.1 update allowed for voting on amendments, which include the AMM.

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