2018-02-16 22:01:13 +00:00
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BSIP: 0031
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Title: Update Short Position's Margin Call Price After Partially Called Or Settled
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Author: Abit More <https://github.com/abitmore>
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Status: Draft
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Type: Protocol
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Created: 2018-02-16
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Discussion: https://github.com/bitshares/bitshares-core/issues/343,
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https://github.com/bitshares/bitshares-core/issues/649
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Replaces: -
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Worker: To be done
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# Abstract
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Currently, when a short position get partially called or settled, the call
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price won't change, that said, even if its actual collateral ratio is higher
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than others, higher than minimum required, it will still be selling collateral
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at a low price, taking precedence over other short positions.
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This behavior is causing several issues:
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* it's somehow unfair, thus brought bad experience to shorters, and
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* it prevents black swan event from being triggered in time when needed,
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because the collateral ratio of the 2nd even overall short positions may
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be too low but not being checked, thus risks the pegging system.
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This BSIP proposes a mechanism to improve this situation.
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# Motivation
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Make the exchange system more user-friendly.
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2018-02-18 13:23:02 +00:00
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# Rationale
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2018-02-16 22:01:13 +00:00
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To attract more users, the system should be fair, should be well balanced.
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It's common sense that short positions with least collateral ratio should
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get margin called first. This can be achieved if always update the margin
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call price after every fill.
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# Specifications
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In `fill_order( const call_order_object& ...)` function of `database` class,
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update `call_price` field of `call_order_object` after debt or collateral
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changed to a non-zero value.
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In addtion, after `call_price` get updated, the iterators initialized with
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`by_price` index may be invalidated, so need to review / revise involved code,
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E.G. `check_call_orders(...)` function of `database` class.
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# Discussion
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[to be added if any]
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# Summary for Shareholders
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[to be added if any]
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# Copyright
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This document is placed in the public domain.
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# See Also
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* https://github.com/bitshares/bitshares-core/issues/343
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* https://github.com/bitshares/bitshares-core/issues/649
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* https://bitsharestalk.org/index.php?topic=25926.0
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