[katran]: adding gating logic for introspection #48
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ops. older version. going to reupload correct one |
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katran/lib/KatranLb.cpp
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| @@ -39,6 +39,8 @@ constexpr int kFirstElem = 0; | |||
| constexpr int kError = -1; | |||
| constexpr uint32_t kMaxQuicId = 65535; // 2^16-1 | |||
| constexpr folly::StringPiece kEmptyString = ""; | |||
| constexpr uint64_t kEnabled = 1; | |||
| constexpr uint64_t kDisabled = 1; | |||
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enabled and disabled have the same value.
Thoughts on making them an enum instead?
For example, something along the lines of:
enum IntospectionControl : uint8_t { ENABLED, DISABLED}
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ops. missed during merge. let me fix it in a few
this diff is adding default katran's introspection behavior by adding gating logic in forwarding plane. before this diff, if katran is compiled w/ introspection enabled, it would unconditionally send data to userspace for triggered events. even if userspace does not want to receive any data (e.g. limit set to 0 etc). the issue is that if somehow we have high rate of events (e.g. synflood w/ lru trashing) - single core in userspace (which is responsible for reading data from perfpipe and dropping it (as limit is set to 0)) would be pegged. hence by default it is dangerous to run introspection (and today strategy is to deploy katran w/ introspection enabled when needed; which could be suboptimal, as it would require restart and issue could go away). proposed diff adds gatekeeper in bpf code, which would prevent sending data to userspace in a first place if it is not requested. the cost of this GK is +20 bpf instructions and +1 array lookup. which is not that much and would allow to have introspection code deployed unconditionally and enable dumping when needed w/o any restart. as w/ original introspection code this new logic works only if katran was compiled w/ KATRAN_INTROSPECTION define/flag Tested by: katran_tester. made sure that if gk value is set to 1 (by default) we still have pcap files generated w/ packets which have triggered LRU miss. and if it set to 0 - these files are empty
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Summary: After diving in all the build system I found that the first error mentioned in #219 and #220 ``` 1597 | static_assert(formattable_char, "Mixing character types is disallowed."); ``` Was basically happening while compiling folly, after compiling it by itself I noticed this didn't happened, so I found that there was an issue with the fmt dependencies, removing the one that was downloaded by katran The issue mentioned in: #221 Was because katran was configured to use C++14 by default, and some of the libraries of folly require C++17, updated our requirements. Test Plan: TEST Output: ``` Test project /home/ubuntu/ivanmorett/katran/_build/build/katran/lib/tests Start 1: IpHelpersTests.testV4ParsingBe 1/56 Test #1: IpHelpersTests.testV4ParsingBe ....................... Passed 0.01 sec Start 2: IpHelpersTests.testV4ParsingInt 2/56 Test #2: IpHelpersTests.testV4ParsingInt ...................... Passed 0.01 sec Start 3: IpHelpersTests.testV6ParsingBe 3/56 Test #3: IpHelpersTests.testV6ParsingBe ....................... Passed 0.01 sec Start 4: IpHelpersTests.testV6ParsingInt 4/56 Test #4: IpHelpersTests.testV6ParsingInt ...................... Passed 0.01 sec Start 5: IpHelpersTests.testIncorrectAddr 5/56 Test #5: IpHelpersTests.testIncorrectAddr ..................... Passed 0.01 sec Start 6: CHHelpersTest.testMaglevCHSameWeight 6/56 Test #6: CHHelpersTest.testMaglevCHSameWeight ................. Passed 0.01 sec Start 7: CHHelpersTest.testMaglevV2CHSameWeight 7/56 Test #7: CHHelpersTest.testMaglevV2CHSameWeight ............... Passed 0.01 sec Start 8: CHHelpersTest.testMaglevCHDiffWeight 8/56 Test #8: CHHelpersTest.testMaglevCHDiffWeight ................. Passed 0.01 sec Start 9: CHHelpersTest.testMaglevV2CHDiffWeight 9/56 Test #9: CHHelpersTest.testMaglevV2CHDiffWeight ............... Passed 0.01 sec Start 10: CHHelpersTest.testMaglevWeightsSumLargerThanRing 10/56 Test #10: CHHelpersTest.testMaglevWeightsSumLargerThanRing ..... Passed 0.01 sec Start 11: CHHelpersTest.testMaglevWeightsSumBelowRingSize 11/56 Test #11: CHHelpersTest.testMaglevWeightsSumBelowRingSize ...... Passed 0.01 sec Start 12: KatranLbTest.testChangeMac 12/56 Test #12: KatranLbTest.testChangeMac ........................... Passed 0.01 sec Start 13: KatranLbTest.testIfIndex 13/56 Test #13: KatranLbTest.testIfIndex ............................. Passed 0.01 sec Start 14: KatranLbTest.testVipHelpers 14/56 Test #14: KatranLbTest.testVipHelpers .......................... Passed 0.14 sec Start 15: KatranLbTest.testAddingInvalidVip 15/56 Test #15: KatranLbTest.testAddingInvalidVip .................... Passed 0.01 sec Start 16: KatranLbTest.testRealHelpers 16/56 Test #16: KatranLbTest.testRealHelpers ......................... Passed 0.01 sec Start 17: KatranLbTest.testRealFlags 17/56 Test #17: KatranLbTest.testRealFlags ........................... Passed 0.01 sec Start 18: KatranLbTest.testVipStatsHelper 18/56 Test #18: KatranLbTest.testVipStatsHelper ...................... Passed 0.01 sec Start 19: KatranLbTest.testLruStatsHelper 19/56 Test #19: KatranLbTest.testLruStatsHelper ...................... Passed 0.01 sec Start 20: KatranLbTest.testLruMissStatsHelper 20/56 Test #20: KatranLbTest.testLruMissStatsHelper .................. Passed 0.01 sec Start 21: KatranLbTest.testHcHelpers 21/56 Test #21: KatranLbTest.testHcHelpers ........................... Passed 0.01 sec Start 22: KatranLbTest.getVipFlags 22/56 Test #22: KatranLbTest.getVipFlags ............................. Passed 0.01 sec Start 23: KatranLbTest.getAllVips 23/56 Test #23: KatranLbTest.getAllVips .............................. Passed 0.01 sec Start 24: KatranLbTest.testUpdateRealsHelper 24/56 Test #24: KatranLbTest.testUpdateRealsHelper ................... Passed 0.07 sec Start 25: KatranLbTest.testUpdateQuicRealsHelper 25/56 Test #25: KatranLbTest.testUpdateQuicRealsHelper ............... Passed 0.06 sec Start 26: KatranLbTest.testUpdateQuicReal 26/56 Test #26: KatranLbTest.testUpdateQuicReal ...................... Passed 0.01 sec Start 27: KatranLbTest.getRealsForVip 27/56 Test #27: KatranLbTest.getRealsForVip .......................... Passed 0.01 sec Start 28: KatranLbTest.getHealthcheckersDst 28/56 Test #28: KatranLbTest.getHealthcheckersDst .................... Passed 0.01 sec Start 29: KatranLbTest.invalidAddressHandling 29/56 Test #29: KatranLbTest.invalidAddressHandling .................. Passed 0.01 sec Start 30: KatranLbTest.addInvalidSrcRoutingRule 30/56 Test #30: KatranLbTest.addInvalidSrcRoutingRule ................ Passed 0.01 sec Start 31: KatranLbTest.addValidSrcRoutingRuleV4 31/56 Test #31: KatranLbTest.addValidSrcRoutingRuleV4 ................ Passed 0.01 sec Start 32: KatranLbTest.addValidSrcRoutingRuleV6 32/56 Test #32: KatranLbTest.addValidSrcRoutingRuleV6 ................ Passed 0.01 sec Start 33: KatranLbTest.addMaxSrcRules 33/56 Test #33: KatranLbTest.addMaxSrcRules .......................... Passed 0.01 sec Start 34: KatranLbTest.delSrcRules 34/56 Test #34: KatranLbTest.delSrcRules ............................. Passed 0.01 sec Start 35: KatranLbTest.clearSrcRules 35/56 Test #35: KatranLbTest.clearSrcRules ........................... Passed 0.01 sec Start 36: KatranLbTest.addFewInvalidNets 36/56 Test #36: KatranLbTest.addFewInvalidNets ....................... Passed 0.01 sec Start 37: KatranLbTest.addInvalidDecapDst 37/56 Test #37: KatranLbTest.addInvalidDecapDst ...................... Passed 0.01 sec Start 38: KatranLbTest.addInvalidDecapDstNet 38/56 Test #38: KatranLbTest.addInvalidDecapDstNet ................... Passed 0.01 sec Start 39: KatranLbTest.addValidDecapDst 39/56 Test #39: KatranLbTest.addValidDecapDst ........................ Passed 0.01 sec Start 40: KatranLbTest.delValidDecapDst 40/56 Test #40: KatranLbTest.delValidDecapDst ........................ Passed 0.01 sec Start 41: KatranLbTest.delInvalidDecapDst 41/56 Test #41: KatranLbTest.delInvalidDecapDst ...................... Passed 0.01 sec Start 42: KatranLbTest.addMaxDecapDst 42/56 Test #42: KatranLbTest.addMaxDecapDst .......................... Passed 0.01 sec Start 43: VipTestF.testBatchUpdateReals 43/56 Test #43: VipTestF.testBatchUpdateReals ........................ Passed 0.04 sec Start 44: VipTestF.testBatchUpdateRealsWeight 44/56 Test #44: VipTestF.testBatchUpdateRealsWeight .................. Passed 0.05 sec Start 45: VipTestF.testGetRealsAndWeight 45/56 Test #45: VipTestF.testGetRealsAndWeight ....................... Passed 0.01 sec Start 46: VipTestF.testGetReals 46/56 Test #46: VipTestF.testGetReals ................................ Passed 0.02 sec Start 47: VipTest.testAddRemoveReal 47/56 Test #47: VipTest.testAddRemoveReal ............................ Passed 0.01 sec Start 48: EventPipeCallbackTest.SimpleCallbackTest 48/56 Test #48: EventPipeCallbackTest.SimpleCallbackTest ............. Passed 0.01 sec Start 49: EventPipeCallbackTest.LargeWriteTest 49/56 Test #49: EventPipeCallbackTest.LargeWriteTest ................. Passed 0.15 sec Start 50: TestMonitoringServiceCore.SimpleAcceptSubscription 50/56 Test #50: TestMonitoringServiceCore.SimpleAcceptSubscription ... Passed 0.01 sec Start 51: TestMonitoringServiceCore.SimpleErrors 51/56 Test #51: TestMonitoringServiceCore.SimpleErrors ............... Passed 0.01 sec Start 52: TestMonitoringServiceCore.EventIntersection 52/56 Test #52: TestMonitoringServiceCore.EventIntersection .......... Passed 0.01 sec Start 53: TestMonitoringServiceCore.RacingClients 53/56 Test #53: TestMonitoringServiceCore.RacingClients .............. Passed 0.01 sec Start 54: TestMonitoringServiceCore.SubscribeAndCancel 54/56 Test #54: TestMonitoringServiceCore.SubscribeAndCancel ......... Passed 0.01 sec Start 55: PcapWriterTest.SingleWriter 55/56 Test #55: PcapWriterTest.SingleWriter .......................... Passed 0.02 sec Start 56: PcapWriterTest.MultiWriter 56/56 Test #56: PcapWriterTest.MultiWriter ........................... Passed 0.01 sec 100% tests passed, 0 tests failed out of 56 Total Test time (real) = 1.04 sec + cd ../testing/ + ctest -v ./CMakeFiles ./CTestTestfile.cmake ./Makefile ./base64helpers-tests './base64helpers-tests[1]_include.cmake' './base64helpers-tests[1]_tests.cmake' ./cmake_install.cmake ./katran_tester ./libbase64_helpers.a ./libbpftester.a ./libkatran_test_provision.a ./libkatran_test_util.a ./libpcap_parser.a ctest: /usr/local/lib/libcurl.so.4: no version information available (required by ctest) Test project /home/ubuntu/ivanmorett/katran/_build/build/katran/lib/testing Start 1: Base64Tests.testEncode 1/2 Test #1: Base64Tests.testEncode ........... Passed 0.01 sec Start 2: Base64Tests.testDecode 2/2 Test #2: Base64Tests.testDecode ........... Passed 0.01 sec 100% tests passed, 0 tests failed out of 2 Total Test time (real) = 0.01 sec + popd ~/ivanmorett/katran/_build ``` Differential Revision: D55108012 Pulled By: lima1756
lima1756
added a commit
that referenced
this pull request
Mar 20, 2024
Summary: After diving in all the build system I found that the first error mentioned in #219 and #220 ``` 1597 | static_assert(formattable_char, "Mixing character types is disallowed."); ``` Was basically happening while compiling folly, after compiling it by itself I noticed this didn't happened, so I found that there was an issue with the fmt dependencies, removing the one that was downloaded by katran The issue mentioned in: #221 Was because katran was configured to use C++14 by default, and some of the libraries of folly require C++17, updated our requirements. Test Plan: TEST Output: ``` Test project /home/ubuntu/ivanmorett/katran/_build/build/katran/lib/tests Start 1: IpHelpersTests.testV4ParsingBe 1/56 Test #1: IpHelpersTests.testV4ParsingBe ....................... Passed 0.01 sec Start 2: IpHelpersTests.testV4ParsingInt 2/56 Test #2: IpHelpersTests.testV4ParsingInt ...................... Passed 0.01 sec Start 3: IpHelpersTests.testV6ParsingBe 3/56 Test #3: IpHelpersTests.testV6ParsingBe ....................... Passed 0.01 sec Start 4: IpHelpersTests.testV6ParsingInt 4/56 Test #4: IpHelpersTests.testV6ParsingInt ...................... Passed 0.01 sec Start 5: IpHelpersTests.testIncorrectAddr 5/56 Test #5: IpHelpersTests.testIncorrectAddr ..................... Passed 0.01 sec Start 6: CHHelpersTest.testMaglevCHSameWeight 6/56 Test #6: CHHelpersTest.testMaglevCHSameWeight ................. Passed 0.01 sec Start 7: CHHelpersTest.testMaglevV2CHSameWeight 7/56 Test #7: CHHelpersTest.testMaglevV2CHSameWeight ............... Passed 0.01 sec Start 8: CHHelpersTest.testMaglevCHDiffWeight 8/56 Test #8: CHHelpersTest.testMaglevCHDiffWeight ................. Passed 0.01 sec Start 9: CHHelpersTest.testMaglevV2CHDiffWeight 9/56 Test #9: CHHelpersTest.testMaglevV2CHDiffWeight ............... Passed 0.01 sec Start 10: CHHelpersTest.testMaglevWeightsSumLargerThanRing 10/56 Test #10: CHHelpersTest.testMaglevWeightsSumLargerThanRing ..... Passed 0.01 sec Start 11: CHHelpersTest.testMaglevWeightsSumBelowRingSize 11/56 Test #11: CHHelpersTest.testMaglevWeightsSumBelowRingSize ...... Passed 0.01 sec Start 12: KatranLbTest.testChangeMac 12/56 Test #12: KatranLbTest.testChangeMac ........................... Passed 0.01 sec Start 13: KatranLbTest.testIfIndex 13/56 Test #13: KatranLbTest.testIfIndex ............................. Passed 0.01 sec Start 14: KatranLbTest.testVipHelpers 14/56 Test #14: KatranLbTest.testVipHelpers .......................... Passed 0.14 sec Start 15: KatranLbTest.testAddingInvalidVip 15/56 Test #15: KatranLbTest.testAddingInvalidVip .................... Passed 0.01 sec Start 16: KatranLbTest.testRealHelpers 16/56 Test #16: KatranLbTest.testRealHelpers ......................... Passed 0.01 sec Start 17: KatranLbTest.testRealFlags 17/56 Test #17: KatranLbTest.testRealFlags ........................... Passed 0.01 sec Start 18: KatranLbTest.testVipStatsHelper 18/56 Test #18: KatranLbTest.testVipStatsHelper ...................... Passed 0.01 sec Start 19: KatranLbTest.testLruStatsHelper 19/56 Test #19: KatranLbTest.testLruStatsHelper ...................... Passed 0.01 sec Start 20: KatranLbTest.testLruMissStatsHelper 20/56 Test #20: KatranLbTest.testLruMissStatsHelper .................. Passed 0.01 sec Start 21: KatranLbTest.testHcHelpers 21/56 Test #21: KatranLbTest.testHcHelpers ........................... Passed 0.01 sec Start 22: KatranLbTest.getVipFlags 22/56 Test #22: KatranLbTest.getVipFlags ............................. Passed 0.01 sec Start 23: KatranLbTest.getAllVips 23/56 Test #23: KatranLbTest.getAllVips .............................. Passed 0.01 sec Start 24: KatranLbTest.testUpdateRealsHelper 24/56 Test #24: KatranLbTest.testUpdateRealsHelper ................... Passed 0.07 sec Start 25: KatranLbTest.testUpdateQuicRealsHelper 25/56 Test #25: KatranLbTest.testUpdateQuicRealsHelper ............... Passed 0.06 sec Start 26: KatranLbTest.testUpdateQuicReal 26/56 Test #26: KatranLbTest.testUpdateQuicReal ...................... Passed 0.01 sec Start 27: KatranLbTest.getRealsForVip 27/56 Test #27: KatranLbTest.getRealsForVip .......................... Passed 0.01 sec Start 28: KatranLbTest.getHealthcheckersDst 28/56 Test #28: KatranLbTest.getHealthcheckersDst .................... Passed 0.01 sec Start 29: KatranLbTest.invalidAddressHandling 29/56 Test #29: KatranLbTest.invalidAddressHandling .................. Passed 0.01 sec Start 30: KatranLbTest.addInvalidSrcRoutingRule 30/56 Test #30: KatranLbTest.addInvalidSrcRoutingRule ................ Passed 0.01 sec Start 31: KatranLbTest.addValidSrcRoutingRuleV4 31/56 Test #31: KatranLbTest.addValidSrcRoutingRuleV4 ................ Passed 0.01 sec Start 32: KatranLbTest.addValidSrcRoutingRuleV6 32/56 Test #32: KatranLbTest.addValidSrcRoutingRuleV6 ................ Passed 0.01 sec Start 33: KatranLbTest.addMaxSrcRules 33/56 Test #33: KatranLbTest.addMaxSrcRules .......................... Passed 0.01 sec Start 34: KatranLbTest.delSrcRules 34/56 Test #34: KatranLbTest.delSrcRules ............................. Passed 0.01 sec Start 35: KatranLbTest.clearSrcRules 35/56 Test #35: KatranLbTest.clearSrcRules ........................... Passed 0.01 sec Start 36: KatranLbTest.addFewInvalidNets 36/56 Test #36: KatranLbTest.addFewInvalidNets ....................... Passed 0.01 sec Start 37: KatranLbTest.addInvalidDecapDst 37/56 Test #37: KatranLbTest.addInvalidDecapDst ...................... Passed 0.01 sec Start 38: KatranLbTest.addInvalidDecapDstNet 38/56 Test #38: KatranLbTest.addInvalidDecapDstNet ................... Passed 0.01 sec Start 39: KatranLbTest.addValidDecapDst 39/56 Test #39: KatranLbTest.addValidDecapDst ........................ Passed 0.01 sec Start 40: KatranLbTest.delValidDecapDst 40/56 Test #40: KatranLbTest.delValidDecapDst ........................ Passed 0.01 sec Start 41: KatranLbTest.delInvalidDecapDst 41/56 Test #41: KatranLbTest.delInvalidDecapDst ...................... Passed 0.01 sec Start 42: KatranLbTest.addMaxDecapDst 42/56 Test #42: KatranLbTest.addMaxDecapDst .......................... Passed 0.01 sec Start 43: VipTestF.testBatchUpdateReals 43/56 Test #43: VipTestF.testBatchUpdateReals ........................ Passed 0.04 sec Start 44: VipTestF.testBatchUpdateRealsWeight 44/56 Test #44: VipTestF.testBatchUpdateRealsWeight .................. Passed 0.05 sec Start 45: VipTestF.testGetRealsAndWeight 45/56 Test #45: VipTestF.testGetRealsAndWeight ....................... Passed 0.01 sec Start 46: VipTestF.testGetReals 46/56 Test #46: VipTestF.testGetReals ................................ Passed 0.02 sec Start 47: VipTest.testAddRemoveReal 47/56 Test #47: VipTest.testAddRemoveReal ............................ Passed 0.01 sec Start 48: EventPipeCallbackTest.SimpleCallbackTest 48/56 Test #48: EventPipeCallbackTest.SimpleCallbackTest ............. Passed 0.01 sec Start 49: EventPipeCallbackTest.LargeWriteTest 49/56 Test #49: EventPipeCallbackTest.LargeWriteTest ................. Passed 0.15 sec Start 50: TestMonitoringServiceCore.SimpleAcceptSubscription 50/56 Test #50: TestMonitoringServiceCore.SimpleAcceptSubscription ... Passed 0.01 sec Start 51: TestMonitoringServiceCore.SimpleErrors 51/56 Test #51: TestMonitoringServiceCore.SimpleErrors ............... Passed 0.01 sec Start 52: TestMonitoringServiceCore.EventIntersection 52/56 Test #52: TestMonitoringServiceCore.EventIntersection .......... Passed 0.01 sec Start 53: TestMonitoringServiceCore.RacingClients 53/56 Test #53: TestMonitoringServiceCore.RacingClients .............. Passed 0.01 sec Start 54: TestMonitoringServiceCore.SubscribeAndCancel 54/56 Test #54: TestMonitoringServiceCore.SubscribeAndCancel ......... Passed 0.01 sec Start 55: PcapWriterTest.SingleWriter 55/56 Test #55: PcapWriterTest.SingleWriter .......................... Passed 0.02 sec Start 56: PcapWriterTest.MultiWriter 56/56 Test #56: PcapWriterTest.MultiWriter ........................... Passed 0.01 sec 100% tests passed, 0 tests failed out of 56 Total Test time (real) = 1.04 sec + cd ../testing/ + ctest -v ./CMakeFiles ./CTestTestfile.cmake ./Makefile ./base64helpers-tests './base64helpers-tests[1]_include.cmake' './base64helpers-tests[1]_tests.cmake' ./cmake_install.cmake ./katran_tester ./libbase64_helpers.a ./libbpftester.a ./libkatran_test_provision.a ./libkatran_test_util.a ./libpcap_parser.a ctest: /usr/local/lib/libcurl.so.4: no version information available (required by ctest) Test project /home/ubuntu/ivanmorett/katran/_build/build/katran/lib/testing Start 1: Base64Tests.testEncode 1/2 Test #1: Base64Tests.testEncode ........... Passed 0.01 sec Start 2: Base64Tests.testDecode 2/2 Test #2: Base64Tests.testDecode ........... Passed 0.01 sec 100% tests passed, 0 tests failed out of 2 Total Test time (real) = 0.01 sec + popd ~/ivanmorett/katran/_build ``` Differential Revision: D55108012 Pulled By: lima1756
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this diff is adding default katran's introspection behavior by adding gating
logic in forwarding plane.
before this diff, if katran is compiled w/ introspection enabled,
it would unconditionally send data to userspace for triggered events.
even if userspace does not want to receive any data (e.g. limit set to 0
etc). the issue is that if somehow we have high rate of events
(e.g. synflood w/ lru trashing) - single core in userspace (which is responsible for reading
data from perfpipe and dropping it (as limit is set to 0)) would be pegged.
hence by default it is dangerous to run introspection (and today strategy is to deploy
katran w/ introspection enabled when needed; which could be suboptimal,
as it would require restart and issue could go away).
proposed diff adds gatekeeper in bpf code, which would prevent sending data to
userspace in a first place if it is not requested. the cost of this GK is
+20 bpf instructions and +1 array lookup. which is not that much and would allow
to have introspection code deployed unconditionally and enable dumping when needed
w/o any restart.
as w/ original introspection code this new logic works only if katran
was compiled w/ KATRAN_INTROSPECTION define/flag
Tested by:
katran_tester. made sure that if gk value is set to 1 (by default)
we still have pcap files generated w/ packets which have triggered LRU miss.
and if it set to 0 - these files are empty