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Re: [PATCH v2 2/3] virtio: increase VIRTQUEUE_MAX_SIZE to 32k
From: |
Michael S. Tsirkin |
Subject: |
Re: [PATCH v2 2/3] virtio: increase VIRTQUEUE_MAX_SIZE to 32k |
Date: |
Tue, 5 Oct 2021 03:16:07 -0400 |
On Mon, Oct 04, 2021 at 09:38:08PM +0200, Christian Schoenebeck wrote:
> Raise the maximum possible virtio transfer size to 128M
> (more precisely: 32k * PAGE_SIZE). See previous commit for a
> more detailed explanation for the reasons of this change.
>
> For not breaking any virtio user, all virtio users transition
> to using the new macro VIRTQUEUE_LEGACY_MAX_SIZE instead of
> VIRTQUEUE_MAX_SIZE, so they are all still using the old value
> of 1k with this commit.
>
> On the long-term, each virtio user should subsequently either
> switch from VIRTQUEUE_LEGACY_MAX_SIZE to VIRTQUEUE_MAX_SIZE
> after checking that they support the new value of 32k, or
> otherwise they should replace the VIRTQUEUE_LEGACY_MAX_SIZE
> macro by an appropriate value supported by them.
>
> Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
I don't think we need this. Legacy isn't descriptive either. Just leave
VIRTQUEUE_MAX_SIZE alone, and come up with a new name for 32k.
> ---
> hw/9pfs/virtio-9p-device.c | 2 +-
> hw/block/vhost-user-blk.c | 6 +++---
> hw/block/virtio-blk.c | 6 +++---
> hw/char/virtio-serial-bus.c | 2 +-
> hw/input/virtio-input.c | 2 +-
> hw/net/virtio-net.c | 12 ++++++------
> hw/scsi/virtio-scsi.c | 2 +-
> hw/virtio/vhost-user-fs.c | 6 +++---
> hw/virtio/vhost-user-i2c.c | 2 +-
> hw/virtio/vhost-vsock-common.c | 2 +-
> hw/virtio/virtio-balloon.c | 2 +-
> hw/virtio/virtio-crypto.c | 2 +-
> hw/virtio/virtio-iommu.c | 2 +-
> hw/virtio/virtio-mem.c | 2 +-
> hw/virtio/virtio-mmio.c | 4 ++--
> hw/virtio/virtio-pmem.c | 2 +-
> hw/virtio/virtio-rng.c | 3 ++-
> include/hw/virtio/virtio.h | 20 +++++++++++++++++++-
> 18 files changed, 49 insertions(+), 30 deletions(-)
>
> diff --git a/hw/9pfs/virtio-9p-device.c b/hw/9pfs/virtio-9p-device.c
> index cd5d95dd51..9013e7df6e 100644
> --- a/hw/9pfs/virtio-9p-device.c
> +++ b/hw/9pfs/virtio-9p-device.c
> @@ -217,7 +217,7 @@ static void virtio_9p_device_realize(DeviceState *dev,
> Error **errp)
>
> v->config_size = sizeof(struct virtio_9p_config) + strlen(s->fsconf.tag);
> virtio_init(vdev, "virtio-9p", VIRTIO_ID_9P, v->config_size,
> - VIRTQUEUE_MAX_SIZE);
> + VIRTQUEUE_LEGACY_MAX_SIZE);
> v->vq = virtio_add_queue(vdev, MAX_REQ, handle_9p_output);
> }
>
> diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c
> index 336f56705c..e5e45262ab 100644
> --- a/hw/block/vhost-user-blk.c
> +++ b/hw/block/vhost-user-blk.c
> @@ -480,9 +480,9 @@ static void vhost_user_blk_device_realize(DeviceState
> *dev, Error **errp)
> error_setg(errp, "queue size must be non-zero");
> return;
> }
> - if (s->queue_size > VIRTQUEUE_MAX_SIZE) {
> + if (s->queue_size > VIRTQUEUE_LEGACY_MAX_SIZE) {
> error_setg(errp, "queue size must not exceed %d",
> - VIRTQUEUE_MAX_SIZE);
> + VIRTQUEUE_LEGACY_MAX_SIZE);
> return;
> }
>
> @@ -491,7 +491,7 @@ static void vhost_user_blk_device_realize(DeviceState
> *dev, Error **errp)
> }
>
> virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK,
> - sizeof(struct virtio_blk_config), VIRTQUEUE_MAX_SIZE);
> + sizeof(struct virtio_blk_config), VIRTQUEUE_LEGACY_MAX_SIZE);
>
> s->virtqs = g_new(VirtQueue *, s->num_queues);
> for (i = 0; i < s->num_queues; i++) {
> diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
> index 9c0f46815c..5883e3e7db 100644
> --- a/hw/block/virtio-blk.c
> +++ b/hw/block/virtio-blk.c
> @@ -1171,10 +1171,10 @@ static void virtio_blk_device_realize(DeviceState
> *dev, Error **errp)
> return;
> }
> if (!is_power_of_2(conf->queue_size) ||
> - conf->queue_size > VIRTQUEUE_MAX_SIZE) {
> + conf->queue_size > VIRTQUEUE_LEGACY_MAX_SIZE) {
> error_setg(errp, "invalid queue-size property (%" PRIu16 "), "
> "must be a power of 2 (max %d)",
> - conf->queue_size, VIRTQUEUE_MAX_SIZE);
> + conf->queue_size, VIRTQUEUE_LEGACY_MAX_SIZE);
> return;
> }
>
> @@ -1214,7 +1214,7 @@ static void virtio_blk_device_realize(DeviceState *dev,
> Error **errp)
> virtio_blk_set_config_size(s, s->host_features);
>
> virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK, s->config_size,
> - VIRTQUEUE_MAX_SIZE);
> + VIRTQUEUE_LEGACY_MAX_SIZE);
>
> s->blk = conf->conf.blk;
> s->rq = NULL;
> diff --git a/hw/char/virtio-serial-bus.c b/hw/char/virtio-serial-bus.c
> index 9ad9111115..2d4285ab53 100644
> --- a/hw/char/virtio-serial-bus.c
> +++ b/hw/char/virtio-serial-bus.c
> @@ -1045,7 +1045,7 @@ static void virtio_serial_device_realize(DeviceState
> *dev, Error **errp)
> config_size = offsetof(struct virtio_console_config, emerg_wr);
> }
> virtio_init(vdev, "virtio-serial", VIRTIO_ID_CONSOLE,
> - config_size, VIRTQUEUE_MAX_SIZE);
> + config_size, VIRTQUEUE_LEGACY_MAX_SIZE);
>
> /* Spawn a new virtio-serial bus on which the ports will ride as devices
> */
> qbus_init(&vser->bus, sizeof(vser->bus), TYPE_VIRTIO_SERIAL_BUS,
> diff --git a/hw/input/virtio-input.c b/hw/input/virtio-input.c
> index 345eb2cce7..b6b77488f2 100644
> --- a/hw/input/virtio-input.c
> +++ b/hw/input/virtio-input.c
> @@ -258,7 +258,7 @@ static void virtio_input_device_realize(DeviceState *dev,
> Error **errp)
> assert(vinput->cfg_size <= sizeof(virtio_input_config));
>
> virtio_init(vdev, "virtio-input", VIRTIO_ID_INPUT,
> - vinput->cfg_size, VIRTQUEUE_MAX_SIZE);
> + vinput->cfg_size, VIRTQUEUE_LEGACY_MAX_SIZE);
> vinput->evt = virtio_add_queue(vdev, 64, virtio_input_handle_evt);
> vinput->sts = virtio_add_queue(vdev, 64, virtio_input_handle_sts);
> }
> diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
> index f74b5f6268..5100978b07 100644
> --- a/hw/net/virtio-net.c
> +++ b/hw/net/virtio-net.c
> @@ -636,7 +636,7 @@ static int virtio_net_max_tx_queue_size(VirtIONet *n)
> return VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE;
> }
>
> - return VIRTQUEUE_MAX_SIZE;
> + return VIRTQUEUE_LEGACY_MAX_SIZE;
> }
>
> static int peer_attach(VirtIONet *n, int index)
> @@ -3365,7 +3365,7 @@ static void virtio_net_device_realize(DeviceState *dev,
> Error **errp)
>
> virtio_net_set_config_size(n, n->host_features);
> virtio_init(vdev, "virtio-net", VIRTIO_ID_NET, n->config_size,
> - VIRTQUEUE_MAX_SIZE);
> + VIRTQUEUE_LEGACY_MAX_SIZE);
>
> /*
> * We set a lower limit on RX queue size to what it always was.
> @@ -3373,23 +3373,23 @@ static void virtio_net_device_realize(DeviceState
> *dev, Error **errp)
> * help from us (using virtio 1 and up).
> */
> if (n->net_conf.rx_queue_size < VIRTIO_NET_RX_QUEUE_MIN_SIZE ||
> - n->net_conf.rx_queue_size > VIRTQUEUE_MAX_SIZE ||
> + n->net_conf.rx_queue_size > VIRTQUEUE_LEGACY_MAX_SIZE ||
> !is_power_of_2(n->net_conf.rx_queue_size)) {
> error_setg(errp, "Invalid rx_queue_size (= %" PRIu16 "), "
> "must be a power of 2 between %d and %d.",
> n->net_conf.rx_queue_size, VIRTIO_NET_RX_QUEUE_MIN_SIZE,
> - VIRTQUEUE_MAX_SIZE);
> + VIRTQUEUE_LEGACY_MAX_SIZE);
> virtio_cleanup(vdev);
> return;
> }
>
> if (n->net_conf.tx_queue_size < VIRTIO_NET_TX_QUEUE_MIN_SIZE ||
> - n->net_conf.tx_queue_size > VIRTQUEUE_MAX_SIZE ||
> + n->net_conf.tx_queue_size > VIRTQUEUE_LEGACY_MAX_SIZE ||
> !is_power_of_2(n->net_conf.tx_queue_size)) {
> error_setg(errp, "Invalid tx_queue_size (= %" PRIu16 "), "
> "must be a power of 2 between %d and %d",
> n->net_conf.tx_queue_size, VIRTIO_NET_TX_QUEUE_MIN_SIZE,
> - VIRTQUEUE_MAX_SIZE);
> + VIRTQUEUE_LEGACY_MAX_SIZE);
> virtio_cleanup(vdev);
> return;
> }
> diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
> index 5e5e657e1d..f204e8878a 100644
> --- a/hw/scsi/virtio-scsi.c
> +++ b/hw/scsi/virtio-scsi.c
> @@ -973,7 +973,7 @@ void virtio_scsi_common_realize(DeviceState *dev,
> int i;
>
> virtio_init(vdev, "virtio-scsi", VIRTIO_ID_SCSI,
> - sizeof(VirtIOSCSIConfig), VIRTQUEUE_MAX_SIZE);
> + sizeof(VirtIOSCSIConfig), VIRTQUEUE_LEGACY_MAX_SIZE);
>
> if (s->conf.num_queues == VIRTIO_SCSI_AUTO_NUM_QUEUES) {
> s->conf.num_queues = 1;
> diff --git a/hw/virtio/vhost-user-fs.c b/hw/virtio/vhost-user-fs.c
> index ae1672d667..decc5def39 100644
> --- a/hw/virtio/vhost-user-fs.c
> +++ b/hw/virtio/vhost-user-fs.c
> @@ -209,9 +209,9 @@ static void vuf_device_realize(DeviceState *dev, Error
> **errp)
> return;
> }
>
> - if (fs->conf.queue_size > VIRTQUEUE_MAX_SIZE) {
> + if (fs->conf.queue_size > VIRTQUEUE_LEGACY_MAX_SIZE) {
> error_setg(errp, "queue-size property must be %u or smaller",
> - VIRTQUEUE_MAX_SIZE);
> + VIRTQUEUE_LEGACY_MAX_SIZE);
> return;
> }
>
> @@ -220,7 +220,7 @@ static void vuf_device_realize(DeviceState *dev, Error
> **errp)
> }
>
> virtio_init(vdev, "vhost-user-fs", VIRTIO_ID_FS,
> - sizeof(struct virtio_fs_config), VIRTQUEUE_MAX_SIZE);
> + sizeof(struct virtio_fs_config), VIRTQUEUE_LEGACY_MAX_SIZE);
>
> /* Hiprio queue */
> fs->hiprio_vq = virtio_add_queue(vdev, fs->conf.queue_size,
> vuf_handle_output);
> diff --git a/hw/virtio/vhost-user-i2c.c b/hw/virtio/vhost-user-i2c.c
> index eeb1d8853a..b248ddbe93 100644
> --- a/hw/virtio/vhost-user-i2c.c
> +++ b/hw/virtio/vhost-user-i2c.c
> @@ -221,7 +221,7 @@ static void vu_i2c_device_realize(DeviceState *dev, Error
> **errp)
> }
>
> virtio_init(vdev, "vhost-user-i2c", VIRTIO_ID_I2C_ADAPTER, 0,
> - VIRTQUEUE_MAX_SIZE);
> + VIRTQUEUE_LEGACY_MAX_SIZE);
>
> i2c->vhost_dev.nvqs = 1;
> i2c->vq = virtio_add_queue(vdev, 4, vu_i2c_handle_output);
> diff --git a/hw/virtio/vhost-vsock-common.c b/hw/virtio/vhost-vsock-common.c
> index a81fa884a8..73e6b72bba 100644
> --- a/hw/virtio/vhost-vsock-common.c
> +++ b/hw/virtio/vhost-vsock-common.c
> @@ -201,7 +201,7 @@ void vhost_vsock_common_realize(VirtIODevice *vdev, const
> char *name)
> VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
>
> virtio_init(vdev, name, VIRTIO_ID_VSOCK,
> - sizeof(struct virtio_vsock_config), VIRTQUEUE_MAX_SIZE);
> + sizeof(struct virtio_vsock_config),
> VIRTQUEUE_LEGACY_MAX_SIZE);
>
> /* Receive and transmit queues belong to vhost */
> vvc->recv_vq = virtio_add_queue(vdev, VHOST_VSOCK_QUEUE_SIZE,
> diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
> index 067c73223d..890fb15ed3 100644
> --- a/hw/virtio/virtio-balloon.c
> +++ b/hw/virtio/virtio-balloon.c
> @@ -886,7 +886,7 @@ static void virtio_balloon_device_realize(DeviceState
> *dev, Error **errp)
> int ret;
>
> virtio_init(vdev, "virtio-balloon", VIRTIO_ID_BALLOON,
> - virtio_balloon_config_size(s), VIRTQUEUE_MAX_SIZE);
> + virtio_balloon_config_size(s), VIRTQUEUE_LEGACY_MAX_SIZE);
>
> ret = qemu_add_balloon_handler(virtio_balloon_to_target,
> virtio_balloon_stat, s);
> diff --git a/hw/virtio/virtio-crypto.c b/hw/virtio/virtio-crypto.c
> index 1e70d4d2a8..e13b6091d6 100644
> --- a/hw/virtio/virtio-crypto.c
> +++ b/hw/virtio/virtio-crypto.c
> @@ -811,7 +811,7 @@ static void virtio_crypto_device_realize(DeviceState
> *dev, Error **errp)
> }
>
> virtio_init(vdev, "virtio-crypto", VIRTIO_ID_CRYPTO,
> vcrypto->config_size,
> - VIRTQUEUE_MAX_SIZE);
> + VIRTQUEUE_LEGACY_MAX_SIZE);
> vcrypto->curr_queues = 1;
> vcrypto->vqs = g_malloc0(sizeof(VirtIOCryptoQueue) *
> vcrypto->max_queues);
> for (i = 0; i < vcrypto->max_queues; i++) {
> diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
> index ca360e74eb..845df78842 100644
> --- a/hw/virtio/virtio-iommu.c
> +++ b/hw/virtio/virtio-iommu.c
> @@ -974,7 +974,7 @@ static void virtio_iommu_device_realize(DeviceState *dev,
> Error **errp)
> VirtIOIOMMU *s = VIRTIO_IOMMU(dev);
>
> virtio_init(vdev, "virtio-iommu", VIRTIO_ID_IOMMU,
> - sizeof(struct virtio_iommu_config), VIRTQUEUE_MAX_SIZE);
> + sizeof(struct virtio_iommu_config),
> VIRTQUEUE_LEGACY_MAX_SIZE);
>
> memset(s->iommu_pcibus_by_bus_num, 0,
> sizeof(s->iommu_pcibus_by_bus_num));
>
> diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c
> index 1d9d01b871..7a39550cde 100644
> --- a/hw/virtio/virtio-mem.c
> +++ b/hw/virtio/virtio-mem.c
> @@ -738,7 +738,7 @@ static void virtio_mem_device_realize(DeviceState *dev,
> Error **errp)
> vmem->bitmap = bitmap_new(vmem->bitmap_size);
>
> virtio_init(vdev, TYPE_VIRTIO_MEM, VIRTIO_ID_MEM,
> - sizeof(struct virtio_mem_config), VIRTQUEUE_MAX_SIZE);
> + sizeof(struct virtio_mem_config), VIRTQUEUE_LEGACY_MAX_SIZE);
> vmem->vq = virtio_add_queue(vdev, 128, virtio_mem_handle_request);
>
> host_memory_backend_set_mapped(vmem->memdev, true);
> diff --git a/hw/virtio/virtio-mmio.c b/hw/virtio/virtio-mmio.c
> index 7b3ebca178..ae0cc223e9 100644
> --- a/hw/virtio/virtio-mmio.c
> +++ b/hw/virtio/virtio-mmio.c
> @@ -174,7 +174,7 @@ static uint64_t virtio_mmio_read(void *opaque, hwaddr
> offset, unsigned size)
> if (!virtio_queue_get_num(vdev, vdev->queue_sel)) {
> return 0;
> }
> - return VIRTQUEUE_MAX_SIZE;
> + return VIRTQUEUE_LEGACY_MAX_SIZE;
> case VIRTIO_MMIO_QUEUE_PFN:
> if (!proxy->legacy) {
> qemu_log_mask(LOG_GUEST_ERROR,
> @@ -348,7 +348,7 @@ static void virtio_mmio_write(void *opaque, hwaddr
> offset, uint64_t value,
> }
> break;
> case VIRTIO_MMIO_QUEUE_NUM:
> - trace_virtio_mmio_queue_write(value, VIRTQUEUE_MAX_SIZE);
> + trace_virtio_mmio_queue_write(value, VIRTQUEUE_LEGACY_MAX_SIZE);
> virtio_queue_set_num(vdev, vdev->queue_sel, value);
>
> if (proxy->legacy) {
> diff --git a/hw/virtio/virtio-pmem.c b/hw/virtio/virtio-pmem.c
> index 82b54b00c5..5f4d375b58 100644
> --- a/hw/virtio/virtio-pmem.c
> +++ b/hw/virtio/virtio-pmem.c
> @@ -124,7 +124,7 @@ static void virtio_pmem_realize(DeviceState *dev, Error
> **errp)
>
> host_memory_backend_set_mapped(pmem->memdev, true);
> virtio_init(vdev, TYPE_VIRTIO_PMEM, VIRTIO_ID_PMEM,
> - sizeof(struct virtio_pmem_config), VIRTQUEUE_MAX_SIZE);
> + sizeof(struct virtio_pmem_config),
> VIRTQUEUE_LEGACY_MAX_SIZE);
> pmem->rq_vq = virtio_add_queue(vdev, 128, virtio_pmem_flush);
> }
>
> diff --git a/hw/virtio/virtio-rng.c b/hw/virtio/virtio-rng.c
> index 0e91d60106..ab075b22b6 100644
> --- a/hw/virtio/virtio-rng.c
> +++ b/hw/virtio/virtio-rng.c
> @@ -215,7 +215,8 @@ static void virtio_rng_device_realize(DeviceState *dev,
> Error **errp)
> return;
> }
>
> - virtio_init(vdev, "virtio-rng", VIRTIO_ID_RNG, 0, VIRTQUEUE_MAX_SIZE);
> + virtio_init(vdev, "virtio-rng", VIRTIO_ID_RNG, 0,
> + VIRTQUEUE_LEGACY_MAX_SIZE);
>
> vrng->vq = virtio_add_queue(vdev, 8, handle_input);
> vrng->quota_remaining = vrng->conf.max_bytes;
> diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h
> index a37d1f7d52..fe0f13266b 100644
> --- a/include/hw/virtio/virtio.h
> +++ b/include/hw/virtio/virtio.h
> @@ -48,7 +48,25 @@ size_t virtio_feature_get_config_size(const VirtIOFeature
> *features,
>
> typedef struct VirtQueue VirtQueue;
>
> -#define VIRTQUEUE_MAX_SIZE 1024
> +/*
> + * This is meant as transitional measure for VIRTQUEUE_MAX_SIZE's old value
> + * of 1024 to its new value of 32768. On the long-term virtio users should
> + * either switch to VIRTQUEUE_MAX_SIZE, provided they support 32768,
> + * otherwise they should replace this macro on their side with an
> + * appropriate value actually supported by them.
> + *
> + * Once all virtio users switched, this macro will be removed.
> + */
> +#define VIRTQUEUE_LEGACY_MAX_SIZE 1024
> +
> +/*
> + * Reflects the absolute theoretical maximum queue size (in amount of pages)
> + * ever possible, which is actually the maximum queue size allowed by the
> + * virtio protocol. This value therefore construes the maximum transfer size
> + * possible with virtio (multiplied by system dependent PAGE_SIZE); assuming
> + * a typical page size of 4k this would be a maximum transfer size of 128M.
> + */
> +#define VIRTQUEUE_MAX_SIZE 32768
>
> typedef struct VirtQueueElement
> {
> --
> 2.20.1
- Re: [PATCH v2 1/3] virtio: turn VIRTQUEUE_MAX_SIZE into a variable, (continued)
- Re: [PATCH v2 1/3] virtio: turn VIRTQUEUE_MAX_SIZE into a variable, Christian Schoenebeck, 2021/10/05
- Re: [PATCH v2 1/3] virtio: turn VIRTQUEUE_MAX_SIZE into a variable, Stefan Hajnoczi, 2021/10/05
- Re: [PATCH v2 1/3] virtio: turn VIRTQUEUE_MAX_SIZE into a variable, Christian Schoenebeck, 2021/10/05
- Re: [PATCH v2 1/3] virtio: turn VIRTQUEUE_MAX_SIZE into a variable, Stefan Hajnoczi, 2021/10/06
- Re: [PATCH v2 1/3] virtio: turn VIRTQUEUE_MAX_SIZE into a variable, Christian Schoenebeck, 2021/10/06
- Re: [PATCH v2 1/3] virtio: turn VIRTQUEUE_MAX_SIZE into a variable, Stefan Hajnoczi, 2021/10/06
- Re: [PATCH v2 1/3] virtio: turn VIRTQUEUE_MAX_SIZE into a variable, Christian Schoenebeck, 2021/10/07
- Re: [PATCH v2 1/3] virtio: turn VIRTQUEUE_MAX_SIZE into a variable, Stefan Hajnoczi, 2021/10/07
- Re: [PATCH v2 1/3] virtio: turn VIRTQUEUE_MAX_SIZE into a variable, Christian Schoenebeck, 2021/10/08
[PATCH v2 2/3] virtio: increase VIRTQUEUE_MAX_SIZE to 32k, Christian Schoenebeck, 2021/10/04
- Re: [PATCH v2 2/3] virtio: increase VIRTQUEUE_MAX_SIZE to 32k,
Michael S. Tsirkin <=
[PATCH v2 3/3] virtio-9p-device: switch to 32k max. transfer size, Christian Schoenebeck, 2021/10/04
Re: [PATCH v2 0/3] virtio: increase VIRTQUEUE_MAX_SIZE to 32k, David Hildenbrand, 2021/10/05
Re: [PATCH v2 0/3] virtio: increase VIRTQUEUE_MAX_SIZE to 32k, Stefan Hajnoczi, 2021/10/07