In　the　context　of　large-scale　datacenter　networks,　the　distinct　mechanisms　of　these　two　protocols　result　in　mutual　interference　when　TCP　and　RoCE　flows　traverse　shared　segments　of　network.　TCP　may　preempt　the　bandwidth　allocated　to　RoCE,　leading　to　unfair　allocation　of　shared　buffers.　Nevertheless,　due　to　the　cost　trade-off,　the　consideration　of　shared　buffers　becomes　necessary.　Therefore,　isolating　through　traffic　classes　does　not　effectively　address　the　issue.　To　meet　the　challenge,　in　this　paper,　we　present　BufferConcede,　a　switch-based　traffic　control　method　that　allows　TCP　traffic　to　occupy　more　buffer　space　in　non-hybrid　switch,　thereby　weakening　TCP　traffic’s　greediness　for　buffer　space.　We　integrate　it　with　practical　congestion　control　approaches　such　as　DCQCN,　DCTCP.　We　evaluate　BufferConcede　in　both　implementation　and　large-scale　simulations.　Compared　with　state　of　the　act,　BufferConcede　can　reduce　bandwidth　allocation　errors　under　2.0%　and　reduce　the　average　FCT　of　RoCE　traffic　by　approximately　4.8%–10.2%.　©　The　Author(s),　under　exclusive　license　to　Springer　Nature　Switzerland　AG　2025.