diff --git a/.glusterfs.metadata b/.glusterfs.metadata
index 0a7c6b2..94bcb6b 100644
--- a/.glusterfs.metadata
+++ b/.glusterfs.metadata
@@ -1 +1 @@
-20136e3863385f10ef984c1cad5d8bc54ec095ca  SOURCES/glusterfs-9.4.tar.gz
+6e1eeb9623ed694db5b591c7689aa59a1bc53eea  SOURCES/glusterfs-10.0rc0.tar.gz
diff --git a/README.md b/README.md
index 84062f0..423cc28 100644
--- a/README.md
+++ b/README.md
@@ -6,7 +6,7 @@ Branch names follow convention like `c<VERSION>-sig-storage-gluster-<GLUSTERFS-V
 * c6-sig-storage-gluster-5: CentOS-6, glusterfs-5
 * c7-sig-storage-gluster-5: CentOS-7, glusterfs-5
 * c7-sig-storage-gluster-6: CentOS-7, glusterfs-6
-* c8-sig-storage-gluster-7: CentOS-8, glusterfs-ld the src.rpm with:
+* c8-sig-storage-gluster-7: CentOS-8, glusterfs-7
 * ...
 
 Instructions for building the glusterfs package for the CentOS Storage SIG can be found in the following places:
@@ -18,32 +18,32 @@ Instructions for building the glusterfs package for the CentOS Storage SIG can b
 E.g. build a src.rpm with:
     $ rpmbuild -bs \
                --define "_sourcedir $PWD/SOURCES" --define "_srcrpmdir $PWD" \
-               --define "dist .el9s" SPECS/glusterfs.spec
+               --define "dist .el8s" SPECS/glusterfs.spec
 
 Get the lookaside uploader script from ssh://git@git.centos.org/centos-git-common.git
 
 To build:
 
 1. Upload the source tar file to the lookaside cache, e.g.:
-    $ lookaside_upload -f SOURCES/glusterfs-9.3.tar.gz -n glusterfs -b c9s-sig-storage-gluster-9
+    $ lookaside_upload -f SOURCES/glusterfs-10.0rc0.tar.gz -n glusterfs -b c8s-sig-storage-gluster-10
 
 2. update the .glusterfs.metadata with the hash from step 1:
-    $ cat .glusterfs.metadata 
-e9c6a6a482b8e46117c2a6c37b50c569bd62d92e  SOURCES/glusterfs-9.3.tar.gz
+    $ cat .glusterfs.metadata
+e9c6a6a482b8e46117c2a6c37b50c569bd62d92e  SOURCES/glusterfs-10.0rc0.tar.gz
 
 3. commit and push SPECS/glusterfs.spec and .glusterfs.metadata, e.g.:
     $ git add SPECS/glusterfs.spec .glusterfs.metadata
-    $ git push origin c9s-sig-storage-gluster-9
+    $ git push origin c8s-sig-storage-gluster-10
 
 4. retrieve the commit for step 3:
     $ git log|head -n 1
 commit 29f19456be12986e86392652331e3a56ff0a88a0
 
 5. build
-    $ cbs build storage9s-gluster-9-el9s git+https://git.centos.org/rpms/glusterfs.git#29f19456be12986e86392652331e3a56ff0a88a0
+    $ cbs build storage8s-gluster-10-el8s git+https://git.centos.org/rpms/glusterfs.git#29f19456be12986e86392652331e3a56ff0a88a0
 
 
 You can do scratch builds from a source RPM with, e.g.:
-    $ cbs build --scratch storage9s-gluster-9-el9s glusterfs-9.3-2.el9s.src.rpm
+    $ cbs build --scratch storage8s-gluster-10-el8s glusterfs-10.0-0.1.rc0.el8s.src.rpm
 
 
diff --git a/SPECS/glusterfs.spec b/SPECS/glusterfs.spec
index 1be59a4..743704a 100644
--- a/SPECS/glusterfs.spec
+++ b/SPECS/glusterfs.spec
@@ -3,7 +3,7 @@
 %global _for_fedora_koji_builds 1
 
 # uncomment and add '%' to use the prereltag for pre-releases
-# %%global prereltag rc0
+%global prereltag rc0
 
 ##-----------------------------------------------------------------------------
 ## All argument definitions should be placed here and keep them sorted
@@ -68,6 +68,12 @@
 # rpmbuild -ta @PACKAGE_NAME@-@PACKAGE_VERSION@.tar.gz --without libtirpc
 %{?_without_libtirpc:%global _without_libtirpc --without-libtirpc}
 
+# libtcmalloc
+# if you wish to compile an rpm without tcmalloc (i.e. use gluster mempool)
+# rpmbuild -ta glusterfs-10.0rc0.tar.gz --without tcmalloc
+# CentOS Stream 8 does not have gperftools
+%global _without_tcmalloc --without-tcmalloc
+
 # Do not use libtirpc on EL6, it does not have xdr_uint64_t() and xdr_uint32_t
 # Do not use libtirpc on EL7, it does not have xdr_sizeof()
 %if ( 0%{?rhel} && 0%{?rhel} < 8 )
@@ -222,8 +228,8 @@
 Summary:          Distributed File System
 %if ( 0%{_for_fedora_koji_builds} )
 Name:             glusterfs
-Version:          9.4
-Release:          1%{?prereltag:.%{prereltag}}%{?dist}
+Version:          10.0
+Release:          %{?prereltag:0.}1%{?prereltag:.%{prereltag}}%{?dist}
 %else
 Name:             @PACKAGE_NAME@
 Version:          @PACKAGE_VERSION@
@@ -248,6 +254,10 @@ Requires(pre):    shadow-utils
 BuildRequires:    systemd
 %endif
 
+%if ( 0%{!?_without_tcmalloc:1} )
+Requires:         gperftools-libs%{?_isa}
+%endif
+
 Requires:         libglusterfs0%{?_isa} = %{version}-%{release}
 Requires:         libgfrpc0%{?_isa} = %{version}-%{release}
 Requires:         libgfxdr0%{?_isa} = %{version}-%{release}
@@ -266,6 +276,9 @@ BuildRequires:    ncurses-devel readline-devel
 BuildRequires:    libxml2-devel openssl-devel
 BuildRequires:    libaio-devel libacl-devel
 BuildRequires:    python%{_pythonver}-devel
+%if ( 0%{!?_without_tcmalloc:1} )
+BuildRequires:    gperftools-devel
+%endif
 %if ( 0%{?rhel} && 0%{?rhel} < 8 )
 BuildRequires:    python-ctypes
 %endif
@@ -865,7 +878,8 @@ done
         %{?_without_syslog} \
         %{?_with_ipv6default} \
         %{?_without_linux_io_uring} \
-        %{?_without_libtirpc}
+        %{?_without_libtirpc} \
+        %{?_without_tcmalloc}
 
 # fix hardening and remove rpath in shlibs
 %if ( 0%{?fedora} ) || ( 0%{?rhel} && 0%{?rhel} > 6 )
@@ -1393,7 +1407,7 @@ exit 0
      %{_libexecdir}/glusterfs/python/syncdaemon/*
 %dir %{_libexecdir}/glusterfs/scripts
      %{_libexecdir}/glusterfs/scripts/get-gfid.sh
-     %{_libexecdir}/glusterfs/scripts/slave-upgrade.sh
+     %{_libexecdir}/glusterfs/scripts/secondary-upgrade.sh
      %{_libexecdir}/glusterfs/scripts/gsync-upgrade.sh
      %{_libexecdir}/glusterfs/scripts/generate-gfid-file.sh
      %{_libexecdir}/glusterfs/scripts/gsync-sync-gfid
@@ -1651,6 +1665,9 @@ exit 0
 %endif
 
 %changelog
+* Thu Oct 21 2021 Niels de Vos <ndevos@redhat.com> - 10.0-0.1.rc0
+- GlusterFS 10.0 Release Candidate 0
+
 * Tue Oct 5 2021 Niels de Vos <ndevos@redhat.com> - 9.4-1
 - GlusterFS 9.4 GA