We THOUGHT that feeding accurate price for BTS/FIAT will bring stable pegged smart coins. However, market told us that we were wrong. In a downtrend, smart coins are always running with a premium; in a uptrend, smart coins are tend to run with a discount. See this chart: https://coinmarketcap.com/currencies/bitusd/

Without a tight peg, the smart coins are useless -- we won't get mass adoption. Why do we keep the broken rules unchanged?

Apparently we can adjust the input data. We SHOULD adjust the input. When smart coins are running with a premium, we can feed higher BTS price to encourage more shorting and more supply, to reduce the premium. When running with a discount, we feed lower BTS price.

How much offset should we apply to the price so that we can achieve a tight peg? I don't know the exact value. It depends. However, without trying we'll never know.

Please discuss, and act.


BSIP doc: https://github.com/bitshares/bsips/blob/master/bsip-0042.md


Poll workers:

1.14.118 Poll - BSIP42 - Adjust price feed dynamically

1.14.119 Poll - BSIP42 - NO adjustment to price feed

Chinese version: https://bitsharestalk.org/index.php?topic=26820.msg320041#msg320041

This is a protocol upgrade release. All nodes should upgrade before `2018-07-19 14:00:00 UTC`.

Detailed info and binaries for download: https://github.com/bitshares/bitshares-core/releases/tag/2.0.180612

Note: in the previous release ([`2.0.180425`](https://github.com/bitshares/bitshares-core/releases/tag/2.0.180425)) we fixed a serious bug.
* If you're upgrading from `2.0.180425` to `2.0.180612`, you don't need to do anything special;
* if you're upgrading from a release earlier than `2.0.180425` to `2.0.180612`, please check [release notes of 2.0.180425](https://github.com/bitshares/bitshares-core/releases/tag/2.0.180425) to see if you need to perform additional steps.

## Consensus changes

* [BSIP26: Refund Order Creation Fee in Originally Paid Asset when order is cancelled](https://github.com/bitshares/bsips/blob/master/bsip-0026.md)
* [BSIP27: Asset Issuer Reclaim Fee Pool Funds](https://github.com/bitshares/bsips/blob/master/bsip-0027.md)
* [BSIP29: Require owner authority to change asset issuer](https://github.com/bitshares/bsips/blob/master/bsip-0029.md)
* [BSIP30: Always Allow Increasing Collateral Ratio If Debt Not Increased](https://github.com/bitshares/bsips/blob/master/bsip-0030.md)
* [BSIP31: Update Short Position's Margin Call Price After Partially Called Or Settled](https://github.com/bitshares/bsips/blob/master/bsip-0031.md)
* [BSIP32: Always Match Orders At Maker Price](https://github.com/bitshares/bsips/blob/master/bsip-0032.md)
* [BSIP33: Maker Orders With Better Prices Take Precedence](https://github.com/bitshares/bsips/blob/master/bsip-0033.md)
* [BSIP34: Always Trigger Margin Call When Call Price Above Or At Price Feed](https://github.com/bitshares/bsips/blob/master/bsip-0034.md)
* [BSIP35: Mitigate Rounding Issue On Order Matching](https://github.com/bitshares/bsips/blob/master/bsip-0035.md)
* [BSIP36: Remove expired price feeds on maintenance interval](https://github.com/bitshares/bsips/blob/master/bsip-0036.md)
* [BSIP37: Allow new asset name to end with a number](https://github.com/bitshares/bsips/blob/master/bsip-0037.md)
* [BSIP38: Add target collateral ratio option to short positions](https://github.com/bitshares/bsips/blob/master/bsip-0038.md)
* [Bugfix #184: Potential something-for-nothing fill bug](https://github.com/bitshares/bitshares-core/issues/184)
* [Bugfix #214: Proposal cannot contain proposal_update_operation](https://github.com/bitshares/bitshares-core/issues/214)
* [Bugfix #453: Multiple limit order and call order matching issue](https://github.com/bitshares/bitshares-core/issues/453)
* [Bugfix #588: Virtual operations should be excluded from transactions](https://github.com/bitshares/bitshares-core/issues/588)
* [Bugfix #868: Clear price feed data after updated a bitAsset's backing asset ID](https://github.com/bitshares/bitshares-core/issues/868)
* [Bugfix #890: Update median feeds after feed_lifetime_sec changed](https://github.com/bitshares/bitshares-core/issues/890)
* [Bugfix #922 / #931 / #970] Fixed missing checks when updating a smart coin's `bitasset` options E.G. force settlement delay, backing asset ID or etc;
* [Bugfix #942] Fixed missing asset authorities check for "from" account when claiming from a withdraw permission.

## API changes

* `extensions` field of `call_order_update_operation` changed from an array to an object, which affects all related API's E.G. `get_block`, `get_account_history`, `get_relative_account_history` and etc. Due to this, old version of `cli_wallet` won't be compatible with new API nodes when that operation would occur in result.
* [Issue #862, PR #872] Improved pagination of `list_assets` node API
* [Issue #863, PR #871] Node `get_ticker` API now returns time stamp of latest block instead of server time
* [Issue #811, PR #861] Added `get_full_account` command/API to `cli_wallet`


## Other changes

* [[FC PR #36](https://github.com/bitshares/bitshares-fc/pull/36)] Support Boost 1.64-1.65

* [[FC PR #43](https://github.com/bitshares/bitshares-fc/pull/43)] Fixed a memory leak issue in TCP socket destruction

* [[FC PR #44](https://github.com/bitshares/bitshares-fc/pull/44)] Fixed Diffie-Hellman shared key computation (related to memo encryption)

* [Issue #727, PR #880] Added stack trace printing when node crashes (only for boost 1.65)

* [Issue #878, PR #927] Made number of I/O threads configurable (can be manual or auto)

* [Issue #805, PR #840 / #919 / #937] Improved logging level and messages; added logging options about log-rotation

* [Issue #837, PR #848 / #839] Added cli_wallet to Docker

* [PR #938] Fixed an issue that may cause the node to store incorrect block ID to disk when switching forks

* [Issue #582, PR #813] Fixed macOS witness node crash issue when being used as an API server

* [Issue #776, PR #816 / #955] Fixed missing notification to RPC clients when changes occurred on some types of objects

* [Issue #888, PR #954] Fixed an integer overflow issue when checking whether a price feed has expired

* [Issue #864, PR #865] Fixed a `cli_wallet` transaction signing issue when creating proposals with transaction builder

* [Issue #859, PR #801 / #817] Fixed macOS and Ninja build errors introduced in last release

* [Issue #136, PR #928] Fixed an asset supply calculation error in test case

* [Issue #943, PR #869 / #945] Improved a few assertion error messages

* [PR #850] Removed unused asset cache from `cli_wallet`

* [PR #918] Fixed in-code documentation for `set_desired_witness_and_committee_member_count` command/API in `cli_wallet`

* [PR #804] Refactored `node.cpp` and `application.cpp` for easier testing

* [PR #851 / #853 / #854 / #855] Fixed several compiler warnings

## Contributors

* [@abitmore](https://github.com/abitmore)
* [@jmjatlanta](https://github.com/jmjatlanta)
* [@oxarbitrage](https://github.com/oxarbitrage)
* [@pmconrad](https://github.com/pmconrad)
* [@xeroc](https://github.com/xeroc)
* [@cifer-lee](https://github.com/cifer-lee)
* [@ihla](https://github.com/ihla)
* [@zhuliting](https://github.com/zhuliting)
* [@Zapata](https://github.com/Zapata)

地址 http://www.bitshares-scaner.org/

公告 https://steemit.com/blockchain/@blockchain-de/bitshares-blockchain-explorer

看起来不错，但需要改进

TESTNET Protocol upgrade (Hard fork) time is scheduled at `Thu, 31 May 2018 14:00:00 UTC`.

Testnet nodes (especially witnesses and public seed nodes and API nodes) please upgrade in time (before the scheduled time).

Github: https://github.com/bitshares/bitshares-core/releases/tag/test-2.0.180525

Details about this release:

### 1. Protocol upgrade (hard fork) related:

* [Bugfix #922 / #931 / #970] Fixed missing checks when updating a smart coin's `bitasset` options E.G. force settlement delay, backing asset ID or etc;

* [Bugfix #935] Fixed missing margin call checks introduced in fix for #868 and #890 in last testnet release.

* [Bugfix #942] Fixed missing asset authorities check for "from" account when claiming from a withdraw permission.

### 2. Other updates (including the ones done in last testnet release but not included in the release notes)

* [FC repository PR #36] Support Boost 1.64-1.65

* [FC repository PR #43] Fixed a memory leak issue in TCP socket destruction

* [FC repository PR #44] Fixed Diffie-Hellman shared key computation (related to memo encryption)

* [PR #938] Fixed an issue that may cause the node to store incorrect block ID to disk when switching forks

* [Issue #582, PR #813] Fixed macOS witness node crash issue when being used as an API server

* [Issue #776, PR #816 / #955] Fixed missing notification to RPC clients when changes occurred on some types of objects

* [Issue #888, PR #954] Fixed an integer overflow issue when checking whether a price feed has expired

* [Issue #864, PR #865] Fixed a `cli_wallet` transaction signing issue when creating proposals with transaction builder

* [Issue #859, PR #801 / #817] Fixed macOS and Ninja build errors introduced in last release

* [Iuuse #136, PR #928] Fixed an asset supply calculation error in test case

* [Issue #805, PR #840 / #919 / #937] Improved logging level and messages; added logging options about log-rotation

* [Issue #943, PR #869 / #945] Improved a few assertion error messages

* [Issue #727, PR #880] Added stack trace printing when node crashes (only for boost 1.65)

* [Issue #878, PR #927] Made number of IO threads configurable (can be manual or auto)

* [Issue #862, PR #872] Improved pagination of `list_assets` node API

* [Issue #863, PR #871] Node `get_ticker` API now returns time stamp of latest block instead of server time

* [Issue #811, PR #861] Added `get_full_account` command/API to `cli_wallet`

* [PR #850] Removed unused asset cache from `cli_wallet`

* [PR #918] Fixed in-code documentation for `set_desired_witness_and_committee_member_count` command/API in `cli_wallet`

* [PR #804] Refactored `node.cpp` and `application.cpp` for easier testing

* [PR #851 / #853 / #854 / #855] Fixed several compiler warnings

BitAssets' MCR (maintenance collateral ratio) is calculated from price feeds (actually it's the median of feeds), it can change when feed changes, although rarely changes (according to current use cases in production aka BitShares mainnet, but perhaps there are potential new use cases which need to change it frequently).

MCR affects all margin positions. When MCR increased, more short positions will be put into margin call territory; when MCR decreased, more short positions will be pull out of margin call territory.

So, ideally, when MCR changed, all short positions should be reevaluated.

Since the quantity of short positions can be very large, for better performance, a caching mechanism is used in current system, aka "call price". When a short position is created, we calculate its call price with current MCR; when its collateral and/or debt got updated, we update its call price according to current MCR. When median feed price reached call price, the short position is put into margin call territory; when feed price changed backwards, the short position is pull out of margin call territory.

However, in current system, we don't refresh the "call price" cache when MCR changed, that said, existing short positions' call prices can be inconsistent with latest MCR. In the meanwhile, call prices of new positions or updated positions will be always up-to-date as long as MCR didn't change. This may lead to unintended margin calls when MCR decreased, or unintended inability to call when MCR increased.

By the way, BSIP31 partially solved the cache refreshing issue: before BSIP31, when a short position is partially called or settled, its call price won't be updated; after BSIP31, it will. https://github.com/bitshares/bsips/blob/master/bsip-0031.md

Another related feature is BSIP38, using "target_collateral_ratio" option will effectively avoid unintended margin calls, somewhat of double insurance. However, if a borrower is not using "target_collateral_ratio" option, her position can be called unintendedly after MCR decreased. https://github.com/bitshares/bsips/blob/master/bsip-0038.md

Now come back to the MCR topic.

To solve the cache inconsistency issue, we have options:

1. totally drop the caching mechanism, calculate call prices on the fly (may impact order matching performance)

2. update "call price" cache immediately when MCR changed (may impact performance since possibly need to update lots of data at a time)

3. update "call price" cache at maintenance interval since maintenance interval is meant to be used to process mass calculation

With the 3rd approach,

3.1 if we don't change MCR update behavior, aka update "current effective" MCR directly when feed changed, then the call price cache will be still inconsistent before maintenance interval;

3.2 we can defer MCR update to maintenance interval, that said, when detected a MCR change due to feed change or asset option e.g. feed lifetime change, don't apply the MCR update immediately, but apply it in next maintenance interval. With this approach, the call price data will be always consistent to "current effective" MCR.
  * pros: data consistency
  * cons: probably poorer user experience (UX), since users (usually asset issuers and feed producers) need to wait when wanted to update MCR.


Summary:
I recommend the 3.2 approach: defer MCR update to maintenance interval, update call price cache every time after MCR updated.
Update: at present I tend to adopt option 1. Actually, we can also try to move the caching to median price feed.

Thoughts?

This is a repost of https://steemit.com/bitshares/@abit/bitshares-testnet-release-test-2-0-180510

New HARD FORK release for [BitShares](https://bitshares.org/) [Open Public TestNet](https://testnet.bitshares.eu) is out, version [test-2.0.180510](https://github.com/bitshares/bitshares-core/releases/tag/test-2.0.180510).

Hard fork time is scheduled at `Sat, 19 May 2018 13:58:00 UTC`.

Testnet nodes please upgrade, ALL PEOPLE please help test.

Mainnet release will be published after test is done, estimated date is around Tue, 12 June.

## API changes:

* `extensions` field of `call_order_update_operation` changed from an array to an object, which affects all related API's E.G. `get_block`, `get_account_history`, `get_relative_account_history` and etc. Due to this, old version of `cli_wallet` won't be compatible with new API nodes when that operation would occur in result.

## Consensus changes:

* [BSIP26: Refund Order Creation Fee in Originally Paid Asset when order is cancelled](https://github.com/bitshares/bsips/blob/master/bsip-0026.md)
* [BSIP27: Asset Issuer Reclaim Fee Pool Funds](https://github.com/bitshares/bsips/blob/master/bsip-0027.md)
* [BSIP29: Require owner authority to change asset issuer](https://github.com/bitshares/bsips/blob/master/bsip-0029.md)
* [BSIP30: Always Allow Increasing Collateral Ratio If Debt Not Increased](https://github.com/bitshares/bsips/blob/master/bsip-0030.md)
* [BSIP31: Update Short Position's Margin Call Price After Partially Called Or Settled](https://github.com/bitshares/bsips/blob/master/bsip-0031.md)
* [BSIP32: Always Match Orders At Maker Price](https://github.com/bitshares/bsips/blob/master/bsip-0032.md)
* [BSIP33: Maker Orders With Better Prices Take Precedence](https://github.com/bitshares/bsips/blob/master/bsip-0033.md)
* [BSIP34: Always Trigger Margin Call When Call Price Above Or At Price Feed](https://github.com/bitshares/bsips/blob/master/bsip-0034.md)
* [BSIP35: Mitigate Rounding Issue On Order Matching](https://github.com/bitshares/bsips/blob/master/bsip-0035.md)
* [BSIP36: Remove expired price feeds on maintenance interval](https://github.com/bitshares/bsips/blob/master/bsip-0036.md)
* [BSIP37: Allow new asset name to end with a number](https://github.com/bitshares/bsips/blob/master/bsip-0037.md)
* [BSIP38: Add target collateral ratio option to short positions](https://github.com/bitshares/bsips/blob/master/bsip-0038.md)
* [Bugfix #184: Potential something-for-nothing fill bug](https://github.com/bitshares/bitshares-core/issues/184)
* [Bugfix #214: Proposal cannot contain proposal_update_operation](https://github.com/bitshares/bitshares-core/issues/214)
* [Bugfix #453: Multiple limit order and call order matching issue](https://github.com/bitshares/bitshares-core/issues/453)
* [Bugfix #588: Virtual operations should be excluded from transactions](https://github.com/bitshares/bitshares-core/issues/588)
* [Bugfix #868: Clear price feed data after updated a bitAsset's backing asset ID](https://github.com/bitshares/bitshares-core/issues/868)
* [Bugfix #890: Update median feeds after feed_lifetime_sec changed](https://github.com/bitshares/bitshares-core/issues/890)

Non-consensus changes and other info to be updated.

NOTE:

Nodes please upgrade BEFORE the scheduled hard fork time, e.g. upgrade NOW, but not upgrade after the time. If some active witnesses didn't upgrade in time, there will be unintended forking.

Testnet witnesses who have upgraded please leave a message in this thread.

Testnet witnesses who want more votes please leave a message as well.

这贴是开头，先说一下原则。

大家知道，债仓的最低抵押率和爆仓惩罚比例是由喂价人指定。对于 CNY 等理事会资产来说，是由见证人指定。

从机制上来说，见证人负责调整这两个参数。为了系统更好运行，比如为了更好的锚定，见证人【应该】适时调整参数。

目前所有见证人都使用固定抵押率 175% 和爆仓惩罚 110% ，一方面是历史原因，是 BM 拍脑袋想出的初始数据；一方面是实验性质，看看固定参数是否能达到理想效果；甚至说得难听一点，也可能是大部分见证人比较懒、不作为、没有去优化。

现在，经过两年多运行验证，从结果来看， CNY 锚定效果不甚理想，所以有理由推测，认为固定参数可能也是原因之一。也有不少人提出了各种修改参数的方法，虽然还没有最终结论。当然，去中心化本身就是百家共鸣，不一定有最优方案。

【但是】，很少见到见证人出来讨论这个问题，更别说优化方案。从 DPoS 本身来说，【持票人】有义务推动见证人进行参数优化：不作为的见证人应该下调绩效考核分数、甚至下岗。

1. 应该鼓励、甚至要求见证人进行参数调整方面的努力，并积极实施，不能仅限于讨论。

2. 有编码能力的见证人，自己修改喂价脚本，进行实验；没有编码能力的，积极探索，如何使用他人脚本，以及提供思路和修改方案。

3. 可以小步走。一开始调整小一点，慢慢增加。

4. 去中心化，不一定大家都使用同样的调整算法，最好有几套算法，至少是多种实现。因为参数和价格一样，最终取的是所有见证人的中间值（不是平均值）。使用多种脚本会降低同时出错几率。

【待续】