Improve ApproximateFreeSpaceShare calculation

6 files changed, 16 insertions, 9 deletions

diff --git a/ydb/core/blobstorage/pdisk/blobstorage_pdisk.h b/ydb/core/blobstorage/pdisk/blobstorage_pdisk.h
index aed3d485e0..8692fcf926 100644
--- a/ydb/core/blobstorage/pdisk/blobstorage_pdisk.h
+++ b/ydb/core/blobstorage/pdisk/blobstorage_pdisk.h
@@ -1302,15 +1302,17 @@ struct TEvCheckSpaceResult : public TEventLocal<TEvCheckSpaceResult, TEvBlobStor
     ui32 FreeChunks;
     ui32 TotalChunks; // contains common limit in shared free space mode, Total != Free + Used
     ui32 UsedChunks; // number of chunks allocated by requesting owner
+    ui32 NumSlots; // number of VSlots over PDisk
     TString ErrorReason;
 
     TEvCheckSpaceResult(NKikimrProto::EReplyStatus status, TStatusFlags statusFlags, ui32 freeChunks,
-            ui32 totalChunks, ui32 usedChunks, const TString &errorReason)
+            ui32 totalChunks, ui32 usedChunks, ui32 numSlots, const TString &errorReason)
         : Status(status)
         , StatusFlags(statusFlags)
         , FreeChunks(freeChunks)
         , TotalChunks(totalChunks)
         , UsedChunks(usedChunks)
+        , NumSlots(numSlots)
         , ErrorReason(errorReason)
     {}
 
@@ -1321,6 +1323,7 @@ struct TEvCheckSpaceResult : public TEventLocal<TEvCheckSpaceResult, TEvBlobStor
         str << " FreeChunks# " << FreeChunks;
         str << " TotalChunks# " << TotalChunks;
         str << " UsedChunks# " << UsedChunks;
+        str << " NumSlots# " << NumSlots;
         str << " ErrorReason# \"" << ErrorReason << "\"";
         str << "}";
         return str.Str();
diff --git a/ydb/core/blobstorage/pdisk/blobstorage_pdisk_actor.cpp b/ydb/core/blobstorage/pdisk/blobstorage_pdisk_actor.cpp
index b3d89908b2..3e35c8b6e9 100644
--- a/ydb/core/blobstorage/pdisk/blobstorage_pdisk_actor.cpp
+++ b/ydb/core/blobstorage/pdisk/blobstorage_pdisk_actor.cpp
@@ -596,7 +596,7 @@ public:
 
     void ErrorHandle(NPDisk::TEvCheckSpace::TPtr &ev) {
         PDisk->Mon.CheckSpace.CountRequest();
-        Send(ev->Sender, new NPDisk::TEvCheckSpaceResult(NKikimrProto::CORRUPTED, 0, 0, 0, 0, StateErrorReason));
+        Send(ev->Sender, new NPDisk::TEvCheckSpaceResult(NKikimrProto::CORRUPTED, 0, 0, 0, 0, 0, StateErrorReason));
         PDisk->Mon.CheckSpace.CountResponse();
     }
 
diff --git a/ydb/core/blobstorage/pdisk/blobstorage_pdisk_impl.cpp b/ydb/core/blobstorage/pdisk/blobstorage_pdisk_impl.cpp
index 3732fb1479..fffa12c539 100644
--- a/ydb/core/blobstorage/pdisk/blobstorage_pdisk_impl.cpp
+++ b/ydb/core/blobstorage/pdisk/blobstorage_pdisk_impl.cpp
@@ -1911,6 +1911,7 @@ void TPDisk::CheckSpace(TCheckSpace &evCheckSpace) {
                 GetFreeChunks(evCheckSpace.Owner, evCheckSpace.OwnerGroupType),
                 GetTotalChunks(evCheckSpace.Owner, evCheckSpace.OwnerGroupType),
                 GetUsedChunks(evCheckSpace.Owner, evCheckSpace.OwnerGroupType),
+                AtomicGet(TotalOwners),
                 TString()));
     ActorSystem->Send(evCheckSpace.Sender, result.Release());
     Mon.CheckSpace.CountResponse();
@@ -2883,7 +2884,7 @@ bool TPDisk::PreprocessRequest(TRequestBase *request) {
             if (errStatus != NKikimrProto::OK) {
                 LOG_ERROR_S(*ActorSystem, NKikimrServices::BS_PDISK, err.Str());
                 THolder<NPDisk::TEvCheckSpaceResult> result(new NPDisk::TEvCheckSpaceResult(errStatus,
-                            GetStatusFlags(ev.Owner, ev.OwnerGroupType), 0, 0, 0, err.Str()));
+                            GetStatusFlags(ev.Owner, ev.OwnerGroupType), 0, 0, 0, 0, err.Str()));
                 ActorSystem->Send(ev.Sender, result.Release());
                 Mon.CheckSpace.CountResponse();
                 delete request;
diff --git a/ydb/core/blobstorage/pdisk/mock/pdisk_mock.cpp b/ydb/core/blobstorage/pdisk/mock/pdisk_mock.cpp
index 6e549edd20..ce4fef136b 100644
--- a/ydb/core/blobstorage/pdisk/mock/pdisk_mock.cpp
+++ b/ydb/core/blobstorage/pdisk/mock/pdisk_mock.cpp
@@ -756,7 +756,8 @@ public:
     void Handle(NPDisk::TEvCheckSpace::TPtr ev) {
         auto *msg = ev->Get();
         auto res = std::make_unique<NPDisk::TEvCheckSpaceResult>(NKikimrProto::OK, GetStatusFlags(),
-            Impl.GetNumFreeChunks(), Impl.TotalChunks, Impl.TotalChunks - Impl.GetNumFreeChunks(), TString());
+            Impl.GetNumFreeChunks(), Impl.TotalChunks, Impl.TotalChunks - Impl.GetNumFreeChunks(),
+            Impl.Owners.size(), TString());
         Impl.FindOwner(msg, res); // to ensure correct owner/round
         Send(ev->Sender, res.release());
     }
diff --git a/ydb/core/blobstorage/vdisk/common/vdisk_outofspace.h b/ydb/core/blobstorage/vdisk/common/vdisk_outofspace.h
index 28c351b5c7..9e20f1a00e 100644
--- a/ydb/core/blobstorage/vdisk/common/vdisk_outofspace.h
+++ b/ydb/core/blobstorage/vdisk/common/vdisk_outofspace.h
@@ -44,8 +44,8 @@ namespace NKikimr {
             Update(SelfOrderNum, flags);
         }
 
-        void UpdateLocalFreeSpaceShare(ui64 freeSpaceShareMult1000) {
-            AtomicSet(ApproximateFreeSpaceShareMult1000, static_cast<TAtomicBase>(freeSpaceShareMult1000));
+        void UpdateLocalFreeSpaceShare(ui64 freeSpaceShare24bit) {
+            AtomicSet(ApproximateFreeSpaceShare24bit, freeSpaceShare24bit);
         }
 
         void UpdateLocalUsedChunks(ui32 usedChunks) {
@@ -62,7 +62,7 @@ namespace NKikimr {
 
         // free space share as a fraction of 1 -- [0, 1)
         float GetFreeSpaceShare() const {
-            return static_cast<float>(AtomicGet(ApproximateFreeSpaceShareMult1000)) / static_cast<float>(1000);
+            return static_cast<float>(AtomicGet(ApproximateFreeSpaceShare24bit)) / 16'777'216.0f;
         }
 
         ui32 GetLocalUsedChunks() const {
@@ -75,7 +75,7 @@ namespace NKikimr {
         // Cached global flags (obtained by merging AllVDiskFlags)
         TAtomic GlobalFlags = 0;
         // Approximate free space share (to calculate percentage of free/used space)
-        TAtomic ApproximateFreeSpaceShareMult1000 = 0;
+        TAtomic ApproximateFreeSpaceShare24bit = 0;
         // Total VDisks in the group
         const ui32 TotalVDisks;
         // VDisk order number for self
diff --git a/ydb/core/blobstorage/vdisk/skeleton/skeleton_oos_tracker.cpp b/ydb/core/blobstorage/vdisk/skeleton/skeleton_oos_tracker.cpp
index 8af5bd8dc2..9a5b692796 100644
--- a/ydb/core/blobstorage/vdisk/skeleton/skeleton_oos_tracker.cpp
+++ b/ydb/core/blobstorage/vdisk/skeleton/skeleton_oos_tracker.cpp
@@ -85,7 +85,9 @@ namespace NKikimr {
 
             TotalChunks = msg->TotalChunks;
             FreeChunks = msg->FreeChunks;
-            const ui64 freeSpaceShareMult1000 = ui64(1000) * FreeChunks / Max(ui64(1), TotalChunks);
+            const ui64 a = Min(msg->TotalChunks, msg->FreeChunks / Min(1u, msg->NumSlots));
+            const ui64 b = msg->UsedChunks;
+            const ui64 freeSpaceShareMult1000 = ui64(1 << 24) * a / (a + b);
             VCtx->OutOfSpaceState.UpdateLocal(msg->StatusFlags);
             VCtx->OutOfSpaceState.UpdateLocalFreeSpaceShare(freeSpaceShareMult1000);
             VCtx->OutOfSpaceState.UpdateLocalUsedChunks(msg->UsedChunks);