Add hugetlbfs.max_page_size config option

Allows running fdctl on cloud providers

src/app/fdctl/config.c

@@ -529,6 +529,11 @@ fdctl_cfg_from_env( int *      pargc,
                                  "%s/.huge",
                                  config->hugetlbfs.mount_path ) );
 
+  ulong max_page_sz = fd_cstr_to_shmem_page_sz( config->hugetlbfs.max_page_size );
+  if( FD_UNLIKELY( max_page_sz!=FD_SHMEM_HUGE_PAGE_SZ && max_page_sz!=FD_SHMEM_GIGANTIC_PAGE_SZ ) ) {
+    FD_LOG_ERR(( "[hugetlbfs.max_page_size] must be \"huge\" or \"gigantic\"" ));
+  }
+
   replace( config->log.path, "{user}", config->user );
   replace( config->log.path, "{name}", config->name );
   if( FD_LIKELY( !strcmp( "auto", config->log.colorize ) ) )       config->log.colorize1 = 2;

src/app/fdctl/config.h

@@ -150,6 +150,7 @@ typedef struct {
     char gigantic_page_mount_path[ PATH_MAX ];
     char huge_page_mount_path[ PATH_MAX ];
     char mount_path[ PATH_MAX ];
+    char max_page_size[ 16 ];
   } hugetlbfs;
 
   struct {

src/app/fdctl/config/default.toml

@@ -822,6 +822,12 @@ dynamic_port_range = "8900-9000"
     # writable by the Firedancer user.
     mount_path = "/mnt/.fd"
 
+    # The largest supported page size on the system.  Possible values
+    # are either "huge" (2MiB) or "gigantic" (1GiB).  Larger sizes yield
+    # better performance.  Smaller values may be required on virtualized
+    # environments like cloud providers.
+    max_page_size = "gigantic"
+
 # Tiles are described in detail in the layout section above.  While the
 # layout configuration determines how many of each tile to place on
 # which CPU core to create a functioning system, below is the individual

src/app/fdctl/config_parse.c

@@ -284,6 +284,7 @@ fdctl_pod_to_cfg( config_t * config,
   CFG_POP      ( uint,   layout.exec_tile_count                           );
 
   CFG_POP      ( cstr,   hugetlbfs.mount_path                             );
+  CFG_POP      ( cstr,   hugetlbfs.max_page_size                          );
 
   CFG_POP      ( cstr,   tiles.net.interface                              );
   CFG_POP      ( cstr,   tiles.net.xdp_mode                               );
@@ -462,6 +463,7 @@ fdctl_cfg_validate( config_t * cfg ) {
   CFG_HAS_NON_ZERO ( layout.exec_tile_count );
 
   CFG_HAS_NON_EMPTY( hugetlbfs.mount_path );
+  CFG_HAS_NON_EMPTY( hugetlbfs.max_page_size );
 
   CFG_HAS_NON_EMPTY( tiles.net.xdp_mode );
   CFG_HAS_POW2     ( tiles.net.xdp_rx_queue_size );

src/app/fdctl/run/topos/fd_firedancer.c

@@ -77,6 +77,7 @@ fd_topo_initialize( config_t * config ) {
   int enable_rpc = ( config->rpc.port != 0 );
 
   fd_topo_t * topo = { fd_topob_new( &config->topo, config->name ) };
+  topo->max_page_size = fd_cstr_to_shmem_page_sz( config->hugetlbfs.max_page_size );
 
   /*             topo, name */
   fd_topob_wksp( topo, "net_shred"  );

src/app/fdctl/run/topos/fd_frankendancer.c

@@ -18,6 +18,7 @@ fd_topo_initialize( config_t * config ) {
   ulong shred_tile_cnt  = config->layout.shred_tile_count;
 
   fd_topo_t * topo = { fd_topob_new( &config->topo, config->name ) };
+  topo->max_page_size = fd_cstr_to_shmem_page_sz( config->hugetlbfs.max_page_size );
 
   /*             topo, name */
   fd_topob_wksp( topo, "net_quic"     );

src/app/fddev/load.c

@@ -101,6 +101,7 @@ load_cmd_fn( args_t *         args,
     args->load.connections = config->layout.quic_tile_count;
 
   fd_topo_t * topo = { fd_topob_new( &config->topo, config->name ) };
+  topo->max_page_size = fd_cstr_to_shmem_page_sz( config->hugetlbfs.max_page_size );
   add_bench_topo( topo,
                   args->load.affinity,
                   args->load.benchg,

src/disco/topo/fd_topo.h

@@ -397,6 +397,8 @@ typedef struct fd_topo_t {
 
   ulong          agave_affinity_cnt;
   ulong          agave_affinity_cpu_idx[ FD_TILE_MAX ];
+
+  ulong          max_page_size; /* 2^21 or 2^30 */
 } fd_topo_t;
 
 typedef struct {

src/disco/topo/fd_topob.c

@@ -25,6 +25,8 @@ fd_topob_new( void * mem,
   if( FD_UNLIKELY( strlen( app_name )>=sizeof(topo->app_name) ) ) FD_LOG_ERR(( "app_name too long: %s", app_name ));
   strncpy( topo->app_name, app_name, sizeof(topo->app_name) );
 
+  topo->max_page_size = FD_SHMEM_GIGANTIC_PAGE_SZ;
+
   return topo;
 }
 
@@ -488,8 +490,9 @@ fd_topob_finish( fd_topo_t * topo,
        with an extra align of padding incase gaddr_lo is not aligned. */
     ulong total_wksp_footprint = fd_wksp_footprint( part_max, footprint + fd_topo_workspace_align() + loose_sz );
 
-    ulong page_sz = FD_SHMEM_GIGANTIC_PAGE_SZ;
+    ulong page_sz = topo->max_page_size;
     if( FD_UNLIKELY( total_wksp_footprint < 4 * FD_SHMEM_HUGE_PAGE_SZ ) ) page_sz = FD_SHMEM_HUGE_PAGE_SZ;
+    if( FD_UNLIKELY( page_sz!=FD_SHMEM_HUGE_PAGE_SZ && page_sz!=FD_SHMEM_GIGANTIC_PAGE_SZ ) ) FD_LOG_ERR(( "invalid page_sz" ));
 
     ulong wksp_aligned_footprint = fd_ulong_align_up( total_wksp_footprint, page_sz );